LoreKeeper MCP

# Implementation Tasks ## 1. Update Configuration - [x] 1.1 Add XDG_DATA_HOME detection logic to config.py - [x] 1.2 Update default milvus_db_path to use XDG path with fallback - [x] 1.3 Add backward compatibility check for existing database at old location - [x] 1.4 Add logging when using legacy path for backward compatibility - [x] 1.5 Add warning log when both legacy and XDG locations have databases ## 2. Update Cache Factory - [x] 2.1 Update DEFAULT_MILVUS_DB_PATH in cache/factory.py to use XDG path - [x] 2.2 Consider importing path logic from config.py to avoid duplication ## 3. Update Tests - [x] 3.1 Update test_config.py to verify XDG_DATA_HOME path resolution - [x] 3.2 Update test_config_milvus.py to test fallback behavior - [x] 3.3 Add test for backward compatibility (old path exists, new doesn't) - [x] 3.4 Add test for both locations exist (should prefer XDG, warn about legacy) - [x] 3.5 Update tests that hardcode ~/.lorekeeper paths ## 4. Update Documentation - [x] 4.1 Update README.md default path references (lines ~121, ~193) - [x] 4.2 Update docs/cache.md default path references - [x] 4.3 Update docs/architecture.md config example ## 5. Update Specs - [x] 5.1 Update openspec/specs/database-setup/spec.md to use XDG paths - [x] 5.2 Update openspec/specs/entity-cache/spec.md to use XDG paths ## 6. Validation - [x] 6.1 Run all tests and ensure they pass - [x] 6.2 Test manual scenarios: - [x] Fresh install (no existing database) - [x] Existing database at old location only - [x] Existing database at XDG location only - [x] Databases exist at both locations - [x] XDG_DATA_HOME set - [x] XDG_DATA_HOME not set - [x] Environment variable override - [x] CLI flag override - [x] 6.3 Verify no breaking changes for existing users