feat: refactor User/Bot architecture and implement multi-channel gateway

Major changes:
1. Core Architecture: Decoupled Bots from Users. Bots now have independent lifecycles, member management (bot_members), and dedicated configurations.
2. Channel Gateway:
   - Implemented a unified Channel Manager supporting Feishu, Telegram, and Local (Web/CLI) adapters.
   - Added message processing pipeline to normalize interactions across different platforms.
   - Introduced a Contact system for identity binding and guest access policies.
3. Database & Tooling:
   - Consolidated all migrations into 0001_init with updated schema for bots, channels, and contacts.
   - Optimized sqlc.yaml to automatically track the migrations directory.
4. Agent Enhancements:
   - Introduced ToolContext to provide Agents with platform-aware execution capabilities (e.g., messaging, contact lookups).
   - Added tool logging and fallback mechanisms for toolChoice execution.
5. UI & Docs: Updated frontend stores, UI components, and Swagger documentation to align with the new Bot-centric model.

db/queries/users.sql

@@ -4,7 +4,7 @@ VALUES (
   sqlc.arg(username),
   sqlc.arg(email),
   sqlc.arg(password_hash),
-  sqlc.arg(role),
+  sqlc.arg(role)::user_role,
   sqlc.arg(display_name),
   sqlc.arg(avatar_url),
   sqlc.arg(is_active),
@@ -18,7 +18,7 @@ VALUES (
   sqlc.arg(username),
   sqlc.arg(email),
   sqlc.arg(password_hash),
-  sqlc.arg(role),
+  sqlc.arg(role)::user_role,
   sqlc.arg(display_name),
   sqlc.arg(avatar_url),
   sqlc.arg(is_active),
@@ -38,6 +38,9 @@ RETURNING *;
 -- name: GetUserByUsername :one
 SELECT * FROM users WHERE username = sqlc.arg(username);
 
+-- name: GetUserByIdentity :one
+SELECT * FROM users WHERE username = sqlc.arg(identity) OR email = sqlc.arg(identity);
+
 -- name: GetUserByID :one
 SELECT * FROM users WHERE id = sqlc.arg(id);
 
@@ -48,7 +51,7 @@ VALUES (
   sqlc.arg(username),
   sqlc.arg(email),
   sqlc.arg(password_hash),
-  sqlc.arg(role),
+  sqlc.arg(role)::user_role,
   sqlc.arg(display_name),
   sqlc.arg(avatar_url),
   sqlc.arg(is_active),
@@ -58,3 +61,42 @@ RETURNING *;
 
 -- name: CountUsers :one
 SELECT COUNT(*)::bigint AS count FROM users;
+
+-- name: ListUsers :many
+SELECT * FROM users
+ORDER BY created_at DESC;
+
+
+-- name: UpdateUserProfile :one
+UPDATE users
+SET display_name = $2,
+    avatar_url = $3,
+    is_active = $4,
+    updated_at = now()
+WHERE id = $1
+RETURNING *;
+
+-- name: UpdateUserAdmin :one
+UPDATE users
+SET role = sqlc.arg(role)::user_role,
+    display_name = sqlc.arg(display_name),
+    avatar_url = sqlc.arg(avatar_url),
+    is_active = sqlc.arg(is_active),
+    updated_at = now()
+WHERE id = sqlc.arg(id)
+RETURNING *;
+
+-- name: UpdateUserPassword :one
+UPDATE users
+SET password_hash = $2,
+    updated_at = now()
+WHERE id = $1
+RETURNING *;
+
+-- name: UpdateUserLastLogin :one
+UPDATE users
+SET last_login_at = now(),
+    updated_at = now()
+WHERE id = $1
+RETURNING *;
+