refactor: content-addressed assets, cross-channel multimodal, infra simplification (#63)

* refactor(attachment): multimodal attachment refactor with snapshot schema and storage layer

- Add snapshot schema migration (0008) and update init/versions/snapshots
- Add internal/attachment and internal/channel normalize for unified attachment handling
- Move containerfs provider from internal/media to internal/storage
- Update agent types, channel adapters (Telegram/Feishu), inbound and handlers
- Add containerd snapshot lineage and local_channel tests
- Regenerate sqlc, swagger and SDK

* refactor(media): content-addressed asset system with unified naming

- Replace asset_id foreign key with content_hash as sole identifier
  for bot_history_message_assets (pure soft-link model)
- Remove mime, size_bytes, storage_key from DB; derive at read time
  via media.Resolve from actual storage
- Merge migrations 0008/0009 into single 0008; keep 0001 as canonical schema
- Add Docker initdb script for deterministic migration execution order
- Fix cross-channel real-time image display (Telegram → WebUI SSE)
- Fix message disappearing on refresh (null assets fallback)
- Fix file icon instead of image preview (mime derivation from storage)
- Unify AssetID → ContentHash naming across Go, Agent, and Frontend
- Change storage key prefix from 4-char to 2-char for directory sharding
- Add server-entrypoint.sh for Docker deployment migration handling

* refactor(infra): embedded migrations, Docker simplification, and config consolidation

- Embed SQL migrations into Go binary, removing shell-based migration scripts
- Consolidate config files into conf/ directory (app.example.toml, app.docker.toml, app.dev.toml)
- Simplify Docker setup: remove initdb.d scripts, streamline nginx config and entrypoint
- Remove legacy CLI, feishu-echo commands, and obsolete incremental migration files
- Update install script and docs to require sudo for one-click install
- Add mise tasks for dev environment orchestration

* chore: recover migrations

---------

Co-authored-by: Acbox <acbox0328@gmail.com>

devenv/docker-compose.yml

@@ -0,0 +1,41 @@
+name: "memoh-dev"
+services:
+  postgres:
+    image: postgres:18-alpine
+    container_name: memoh-dev-postgres
+    environment:
+      POSTGRES_DB: memoh
+      POSTGRES_USER: memoh
+      POSTGRES_PASSWORD: memoh123
+      TZ: ${TZ:-UTC}
+    volumes:
+      - postgres_data:/var/lib/postgresql/data
+    ports:
+      - "5432:5432"
+    healthcheck:
+      test: ["CMD-SHELL", "pg_isready -U memoh"]
+      interval: 5s
+      timeout: 3s
+      retries: 5
+    restart: unless-stopped
+
+  qdrant:
+    image: qdrant/qdrant:latest
+    container_name: memoh-dev-qdrant
+    volumes:
+      - qdrant_data:/qdrant/storage
+    ports:
+      - "6333:6333"
+      - "6334:6334"
+    healthcheck:
+      test: ["CMD-SHELL", "timeout 5s bash -c ':> /dev/tcp/127.0.0.1/6333' || exit 1"]
+      interval: 5s
+      timeout: 3s
+      retries: 5
+    restart: unless-stopped
+
+volumes:
+  postgres_data:
+    driver: local
+  qdrant_data:
+    driver: local