Module metadata_cache 

SQLite metadata cache for session files

Caches session metadata with mtime-based invalidation for 90% startup speedup.

Schema:

• session_metadata table: stores parsed metadata + mtime + cache_version
• Indexes: project, mtime for fast queries

Invalidation:

• File watcher detects modification → delete cache entry
• Startup: compare mtime → rescan if stale
• Startup: compare cache_version → auto-clear if mismatch

Cache Version History:

• v1: Initial version (pre-TokenUsage fix)
• v2: Fixed TokenUsage::total() to include cache_read_tokens + cache_write_tokens
• v3: Added token breakdown fields (input_tokens, output_tokens, cache_creation_tokens, cache_read_tokens) to SessionMetadata + real pricing calculation

Structs

CacheStats

Cache statistics

MetadataCache

SQLite-based metadata cache (thread-safe)