Major refactor: Switch to complete local operation

- Remove external AI API dependency (no more OpenAI/Claude API calls)
- Claude Code now does all interpretation and scoring locally
- Zero cost: No API fees
- Complete privacy: No data sent to external servers
- Simplified dependencies: Removed openai crate and ai-analysis feature

Changes:
- ai_interpreter.rs: Simplified to lightweight wrapper
- Cargo.toml: Removed ai-analysis feature and openai dependency
- mcp/base.rs: Updated create_memory_with_ai to accept interpreted_content and priority_score from Claude Code
- memory.rs: Added create_memory_with_interpretation() method
- Documentation: Updated README, QUICKSTART, USAGE to reflect local-only operation
- Added CHANGELOG.md to track changes

How it works now:
User → Claude Code (interprets & scores) → aigpt (stores) → game result

Benefits:
✅ 完全ローカル (Fully local)
✅ ゼロコスト (Zero cost)
✅ プライバシー保護 (Privacy protected)
✅ 高速 (Faster - no network latency)
✅ シンプル (Simpler - fewer dependencies)

CHANGELOG.md

@@ -0,0 +1,70 @@
+# Changelog
+
+## [Unreleased] - 2025-11-05
+
+### 🎉 Major Changes: Complete Local Operation
+
+#### Changed
+- **Removed external AI API dependency**: No longer calls Claude/OpenAI APIs
+- **Claude Code does the interpretation**: AIが解釈するのではなく、Claude Code 自身が解釈
+- **Zero cost**: API料金が一切かからない
+- **Complete privacy**: データが外部に送信されない
+
+#### Technical Details
+- Removed `openai` crate dependency
+- Removed `ai-analysis` feature (no longer needed)
+- Simplified `ai_interpreter.rs` to be a lightweight wrapper
+- Updated `create_memory_with_ai` MCP tool to accept `interpreted_content` and `priority_score` from Claude Code
+- Added `create_memory_with_interpretation()` method to MemoryManager
+- Updated tool descriptions to guide Claude Code on how to interpret and score
+
+#### Benefits
+- ✅ **完全ローカル**: 外部 API 不要
+- ✅ **ゼロコスト**: API 料金なし
+- ✅ **プライバシー**: データ漏洩の心配なし
+- ✅ **シンプル**: 依存関係が少ない
+- ✅ **高速**: ネットワーク遅延なし
+
+#### How It Works Now
+
+1. User: 「今日、新しいアイデアを思いついた」とメモリを作成
+2. Claude Code: 内容を解釈し、スコア (0.0-1.0) を計算
+3. Claude Code: `create_memory_with_ai` ツールを呼び出し、解釈とスコアを渡す
+4. aigpt: メモリを保存し、ゲーム風の結果を返す
+5. Claude Code: ユーザーに結果を表示
+
+#### Migration Notes
+
+For users who were expecting external AI API usage:
+- No API keys needed anymore (ANTHROPIC_API_KEY, OPENAI_API_KEY)
+- Claude Code (local) now does all the interpretation
+- This is actually better: faster, cheaper, more private!
+
+---
+
+## [0.1.0] - Initial Release
+
+### Added
+- Basic memory CRUD operations
+- ChatGPT conversation import
+- stdio MCP server implementation
+- Psychological priority scoring (0.0-1.0)
+- Gamification features (rarity, diagnosis types, XP)
+- Romance companion system
+- 11 MCP tools for Claude Code integration
+
+### Features
+- Memory capacity management (max 100 by default)
+- Automatic pruning of low-priority memories
+- Game-style result displays
+- Companion affection and level system
+- Daily challenges
+- Ranking displays
+
+### Documentation
+- README.md with full examples
+- DESIGN.md with system architecture
+- TECHNICAL_REVIEW.md with evaluation
+- ROADMAP.md with 7-phase plan
+- QUICKSTART.md for immediate usage
+- USAGE.md for detailed instructions