feat: implement 800-character document chunking and stabilize Japanese search build ...

- Implement 800-char text chunking in add_item_text.
- Fix Lindera/BLAS dependency issues on Windows by using pure Rust dummy tokenizer.
- Add unit tests for chunking logic in mcp.rs.
- Update .gitignore to include journals.
- Add implementation journal 20260219-0004.

chore: include lock files, maintenance tools and test scripts in v0.2.5 release

feat: MCPプロトコル完全準拠(SSE/非同期レスポンス対応) & ビルド環境・DLL競合の解消

サイドカー自動起動・監視、llama_server状態API、UI連携、ESLint/Prettier整備、journal追加

chore: comprehensive project restructuring and cleanup ...

- Moved backend source to src/backend
- Consolidated build artifacts to root target/
- Organized assets to resources/ and documentation to document/
- Updated README with detailed architecture and simplified onboarding
- Fixed minor bug in lib.rs database initialization
- Cleaned up obsolete Electron-era files and test scripts

build: update dependencies and gitignore for Sidecar integration

chore: migrate to Tauri/Rust backend with SeaORM and add unit/integration tests ...

- Migrated Electron/Bun backend to Rust (Tauri v2).
- Integrated SeaORM with SQLite and sqlite-vec support.
- Implemented unit tests for LlamaClient and database initialization.
- Added integration tests for MCP handlers.
- Updated documentation (README.md, walkthrough, implementation plan).
- Improved dev environment with launch scripts and tasks.
- Followed user global rules for journaling and gitignore.