refactor(core): codebase quality cleanup

- Remove user-level model settings (chat_model_id, memory_model_id,
  embedding_model_id, max_context_load_time, language) from users table
- Merge migration 0002 into 0001, remove compatibility migrations
- Delete dead conversation/resolver.go (1177 lines, only flow/resolver.go used)
- Remove type aliases (Chat=Conversation, types_alias.go)
- Fix SQL: remove AND false stub, fix UpdateChatTitle model_id,
  reset model IDs in DeleteSettings, add preauth expiry filter,
  add ListMessages limit, remove 10 dead queries
- Extract shared handler helpers (RequireChannelIdentityID, AuthorizeBotAccess)
- Rename internal/router to internal/channel/inbound
- Fix identity confusion: remove UserID->ChannelIdentityID fallbacks
- Fix all _ = var patterns with proper error logging
- Fix error propagation: storeMessages, rescheduleJob, botContainerID
- Fix naming: ModelId->ModelID, active->is_active, Duration semantic fix
- Remove dead code: mcpService, ReplyTarget, callMCPServer, sshShellQuote,
  buildSessionMetadata, ChatRequest.Language, TriggerPayload.ChatID
- Fix code quality: errors.Is(), remove goto, CreateHuman deprecated
- Remove Enable model endpoint and user-level settings CLI commands
- Regenerate sqlc, swagger, SDK

internal/db/sqlc/users.sql.go

@@ -37,7 +37,7 @@ SET username = $1,
     data_root = $8,
     updated_at = now()
 WHERE id = $9
-RETURNING id, username, email, password_hash, role, display_name, avatar_url, data_root, last_login_at, chat_model_id, memory_model_id, embedding_model_id, max_context_load_time, language, is_active, metadata, created_at, updated_at
+RETURNING id, username, email, password_hash, role, display_name, avatar_url, data_root, last_login_at, is_active, metadata, created_at, updated_at
 `
 
 type CreateAccountParams struct {
@@ -75,11 +75,6 @@ func (q *Queries) CreateAccount(ctx context.Context, arg CreateAccountParams) (U
 		&i.AvatarUrl,
 		&i.DataRoot,
 		&i.LastLoginAt,
-		&i.ChatModelID,
-		&i.MemoryModelID,
-		&i.EmbeddingModelID,
-		&i.MaxContextLoadTime,
-		&i.Language,
 		&i.IsActive,
 		&i.Metadata,
 		&i.CreatedAt,
@@ -91,7 +86,7 @@ func (q *Queries) CreateAccount(ctx context.Context, arg CreateAccountParams) (U
 const createUser = `-- name: CreateUser :one
 INSERT INTO users (is_active, metadata)
 VALUES ($1, $2)
-RETURNING id, username, email, password_hash, role, display_name, avatar_url, data_root, last_login_at, chat_model_id, memory_model_id, embedding_model_id, max_context_load_time, language, is_active, metadata, created_at, updated_at
+RETURNING id, username, email, password_hash, role, display_name, avatar_url, data_root, last_login_at, is_active, metadata, created_at, updated_at
 `
 
 type CreateUserParams struct {
@@ -112,11 +107,6 @@ func (q *Queries) CreateUser(ctx context.Context, arg CreateUserParams) (User, e
 		&i.AvatarUrl,
 		&i.DataRoot,
 		&i.LastLoginAt,
-		&i.ChatModelID,
-		&i.MemoryModelID,
-		&i.EmbeddingModelID,
-		&i.MaxContextLoadTime,
-		&i.Language,
 		&i.IsActive,
 		&i.Metadata,
 		&i.CreatedAt,
@@ -126,7 +116,7 @@ func (q *Queries) CreateUser(ctx context.Context, arg CreateUserParams) (User, e
 }
 
 const getAccountByIdentity = `-- name: GetAccountByIdentity :one
-SELECT id, username, email, password_hash, role, display_name, avatar_url, data_root, last_login_at, chat_model_id, memory_model_id, embedding_model_id, max_context_load_time, language, is_active, metadata, created_at, updated_at FROM users WHERE username = $1 OR email = $1
+SELECT id, username, email, password_hash, role, display_name, avatar_url, data_root, last_login_at, is_active, metadata, created_at, updated_at FROM users WHERE username = $1 OR email = $1
 `
 
 func (q *Queries) GetAccountByIdentity(ctx context.Context, identity pgtype.Text) (User, error) {
@@ -142,11 +132,6 @@ func (q *Queries) GetAccountByIdentity(ctx context.Context, identity pgtype.Text
 		&i.AvatarUrl,
 		&i.DataRoot,
 		&i.LastLoginAt,
-		&i.ChatModelID,
-		&i.MemoryModelID,
-		&i.EmbeddingModelID,
-		&i.MaxContextLoadTime,
-		&i.Language,
 		&i.IsActive,
 		&i.Metadata,
 		&i.CreatedAt,
@@ -156,7 +141,7 @@ func (q *Queries) GetAccountByIdentity(ctx context.Context, identity pgtype.Text
 }
 
 const getAccountByUserID = `-- name: GetAccountByUserID :one
-SELECT id, username, email, password_hash, role, display_name, avatar_url, data_root, last_login_at, chat_model_id, memory_model_id, embedding_model_id, max_context_load_time, language, is_active, metadata, created_at, updated_at FROM users WHERE id = $1
+SELECT id, username, email, password_hash, role, display_name, avatar_url, data_root, last_login_at, is_active, metadata, created_at, updated_at FROM users WHERE id = $1
 `
 
 func (q *Queries) GetAccountByUserID(ctx context.Context, userID pgtype.UUID) (User, error) {
@@ -172,41 +157,6 @@ func (q *Queries) GetAccountByUserID(ctx context.Context, userID pgtype.UUID) (U
 		&i.AvatarUrl,
 		&i.DataRoot,
 		&i.LastLoginAt,
-		&i.ChatModelID,
-		&i.MemoryModelID,
-		&i.EmbeddingModelID,
-		&i.MaxContextLoadTime,
-		&i.Language,
-		&i.IsActive,
-		&i.Metadata,
-		&i.CreatedAt,
-		&i.UpdatedAt,
-	)
-	return i, err
-}
-
-const getAccountByUsername = `-- name: GetAccountByUsername :one
-SELECT id, username, email, password_hash, role, display_name, avatar_url, data_root, last_login_at, chat_model_id, memory_model_id, embedding_model_id, max_context_load_time, language, is_active, metadata, created_at, updated_at FROM users WHERE username = $1
-`
-
-func (q *Queries) GetAccountByUsername(ctx context.Context, username pgtype.Text) (User, error) {
-	row := q.db.QueryRow(ctx, getAccountByUsername, username)
-	var i User
-	err := row.Scan(
-		&i.ID,
-		&i.Username,
-		&i.Email,
-		&i.PasswordHash,
-		&i.Role,
-		&i.DisplayName,
-		&i.AvatarUrl,
-		&i.DataRoot,
-		&i.LastLoginAt,
-		&i.ChatModelID,
-		&i.MemoryModelID,
-		&i.EmbeddingModelID,
-		&i.MaxContextLoadTime,
-		&i.Language,
 		&i.IsActive,
 		&i.Metadata,
 		&i.CreatedAt,
@@ -216,7 +166,7 @@ func (q *Queries) GetAccountByUsername(ctx context.Context, username pgtype.Text
 }
 
 const getUserByID = `-- name: GetUserByID :one
-SELECT id, username, email, password_hash, role, display_name, avatar_url, data_root, last_login_at, chat_model_id, memory_model_id, embedding_model_id, max_context_load_time, language, is_active, metadata, created_at, updated_at
+SELECT id, username, email, password_hash, role, display_name, avatar_url, data_root, last_login_at, is_active, metadata, created_at, updated_at
 FROM users
 WHERE id = $1
 `
@@ -234,11 +184,6 @@ func (q *Queries) GetUserByID(ctx context.Context, id pgtype.UUID) (User, error)
 		&i.AvatarUrl,
 		&i.DataRoot,
 		&i.LastLoginAt,
-		&i.ChatModelID,
-		&i.MemoryModelID,
-		&i.EmbeddingModelID,
-		&i.MaxContextLoadTime,
-		&i.Language,
 		&i.IsActive,
 		&i.Metadata,
 		&i.CreatedAt,
@@ -248,7 +193,7 @@ func (q *Queries) GetUserByID(ctx context.Context, id pgtype.UUID) (User, error)
 }
 
 const listAccounts = `-- name: ListAccounts :many
-SELECT id, username, email, password_hash, role, display_name, avatar_url, data_root, last_login_at, chat_model_id, memory_model_id, embedding_model_id, max_context_load_time, language, is_active, metadata, created_at, updated_at FROM users
+SELECT id, username, email, password_hash, role, display_name, avatar_url, data_root, last_login_at, is_active, metadata, created_at, updated_at FROM users
 WHERE username IS NOT NULL
 ORDER BY created_at DESC
 `
@@ -272,11 +217,6 @@ func (q *Queries) ListAccounts(ctx context.Context) ([]User, error) {
 			&i.AvatarUrl,
 			&i.DataRoot,
 			&i.LastLoginAt,
-			&i.ChatModelID,
-			&i.MemoryModelID,
-			&i.EmbeddingModelID,
-			&i.MaxContextLoadTime,
-			&i.Language,
 			&i.IsActive,
 			&i.Metadata,
 			&i.CreatedAt,
@@ -300,7 +240,7 @@ SET role = $1::user_role,
     is_active = $4,
     updated_at = now()
 WHERE id = $5
-RETURNING id, username, email, password_hash, role, display_name, avatar_url, data_root, last_login_at, chat_model_id, memory_model_id, embedding_model_id, max_context_load_time, language, is_active, metadata, created_at, updated_at
+RETURNING id, username, email, password_hash, role, display_name, avatar_url, data_root, last_login_at, is_active, metadata, created_at, updated_at
 `
 
 type UpdateAccountAdminParams struct {
@@ -330,11 +270,6 @@ func (q *Queries) UpdateAccountAdmin(ctx context.Context, arg UpdateAccountAdmin
 		&i.AvatarUrl,
 		&i.DataRoot,
 		&i.LastLoginAt,
-		&i.ChatModelID,
-		&i.MemoryModelID,
-		&i.EmbeddingModelID,
-		&i.MaxContextLoadTime,
-		&i.Language,
 		&i.IsActive,
 		&i.Metadata,
 		&i.CreatedAt,
@@ -348,7 +283,7 @@ UPDATE users
 SET last_login_at = now(),
     updated_at = now()
 WHERE id = $1
-RETURNING id, username, email, password_hash, role, display_name, avatar_url, data_root, last_login_at, chat_model_id, memory_model_id, embedding_model_id, max_context_load_time, language, is_active, metadata, created_at, updated_at
+RETURNING id, username, email, password_hash, role, display_name, avatar_url, data_root, last_login_at, is_active, metadata, created_at, updated_at
 `
 
 func (q *Queries) UpdateAccountLastLogin(ctx context.Context, id pgtype.UUID) (User, error) {
@@ -364,11 +299,6 @@ func (q *Queries) UpdateAccountLastLogin(ctx context.Context, id pgtype.UUID) (U
 		&i.AvatarUrl,
 		&i.DataRoot,
 		&i.LastLoginAt,
-		&i.ChatModelID,
-		&i.MemoryModelID,
-		&i.EmbeddingModelID,
-		&i.MaxContextLoadTime,
-		&i.Language,
 		&i.IsActive,
 		&i.Metadata,
 		&i.CreatedAt,
@@ -382,7 +312,7 @@ UPDATE users
 SET password_hash = $2,
     updated_at = now()
 WHERE id = $1
-RETURNING id, username, email, password_hash, role, display_name, avatar_url, data_root, last_login_at, chat_model_id, memory_model_id, embedding_model_id, max_context_load_time, language, is_active, metadata, created_at, updated_at
+RETURNING id, username, email, password_hash, role, display_name, avatar_url, data_root, last_login_at, is_active, metadata, created_at, updated_at
 `
 
 type UpdateAccountPasswordParams struct {
@@ -403,11 +333,6 @@ func (q *Queries) UpdateAccountPassword(ctx context.Context, arg UpdateAccountPa
 		&i.AvatarUrl,
 		&i.DataRoot,
 		&i.LastLoginAt,
-		&i.ChatModelID,
-		&i.MemoryModelID,
-		&i.EmbeddingModelID,
-		&i.MaxContextLoadTime,
-		&i.Language,
 		&i.IsActive,
 		&i.Metadata,
 		&i.CreatedAt,
@@ -423,7 +348,7 @@ SET display_name = $2,
     is_active = $4,
     updated_at = now()
 WHERE id = $1
-RETURNING id, username, email, password_hash, role, display_name, avatar_url, data_root, last_login_at, chat_model_id, memory_model_id, embedding_model_id, max_context_load_time, language, is_active, metadata, created_at, updated_at
+RETURNING id, username, email, password_hash, role, display_name, avatar_url, data_root, last_login_at, is_active, metadata, created_at, updated_at
 `
 
 type UpdateAccountProfileParams struct {
@@ -451,50 +376,6 @@ func (q *Queries) UpdateAccountProfile(ctx context.Context, arg UpdateAccountPro
 		&i.AvatarUrl,
 		&i.DataRoot,
 		&i.LastLoginAt,
-		&i.ChatModelID,
-		&i.MemoryModelID,
-		&i.EmbeddingModelID,
-		&i.MaxContextLoadTime,
-		&i.Language,
-		&i.IsActive,
-		&i.Metadata,
-		&i.CreatedAt,
-		&i.UpdatedAt,
-	)
-	return i, err
-}
-
-const updateUserStatus = `-- name: UpdateUserStatus :one
-UPDATE users
-SET is_active = $2,
-    updated_at = now()
-WHERE id = $1
-RETURNING id, username, email, password_hash, role, display_name, avatar_url, data_root, last_login_at, chat_model_id, memory_model_id, embedding_model_id, max_context_load_time, language, is_active, metadata, created_at, updated_at
-`
-
-type UpdateUserStatusParams struct {
-	ID       pgtype.UUID `json:"id"`
-	IsActive bool        `json:"is_active"`
-}
-
-func (q *Queries) UpdateUserStatus(ctx context.Context, arg UpdateUserStatusParams) (User, error) {
-	row := q.db.QueryRow(ctx, updateUserStatus, arg.ID, arg.IsActive)
-	var i User
-	err := row.Scan(
-		&i.ID,
-		&i.Username,
-		&i.Email,
-		&i.PasswordHash,
-		&i.Role,
-		&i.DisplayName,
-		&i.AvatarUrl,
-		&i.DataRoot,
-		&i.LastLoginAt,
-		&i.ChatModelID,
-		&i.MemoryModelID,
-		&i.EmbeddingModelID,
-		&i.MaxContextLoadTime,
-		&i.Language,
 		&i.IsActive,
 		&i.Metadata,
 		&i.CreatedAt,
@@ -526,7 +407,7 @@ ON CONFLICT (username) DO UPDATE SET
   is_active = EXCLUDED.is_active,
   data_root = EXCLUDED.data_root,
   updated_at = now()
-RETURNING id, username, email, password_hash, role, display_name, avatar_url, data_root, last_login_at, chat_model_id, memory_model_id, embedding_model_id, max_context_load_time, language, is_active, metadata, created_at, updated_at
+RETURNING id, username, email, password_hash, role, display_name, avatar_url, data_root, last_login_at, is_active, metadata, created_at, updated_at
 `
 
 type UpsertAccountByUsernameParams struct {
@@ -564,11 +445,6 @@ func (q *Queries) UpsertAccountByUsername(ctx context.Context, arg UpsertAccount
 		&i.AvatarUrl,
 		&i.DataRoot,
 		&i.LastLoginAt,
-		&i.ChatModelID,
-		&i.MemoryModelID,
-		&i.EmbeddingModelID,
-		&i.MaxContextLoadTime,
-		&i.Language,
 		&i.IsActive,
 		&i.Metadata,
 		&i.CreatedAt,