337f902a7e
Replace the standalone JSON file persistence layer with SessionDB (~/.hermes/state.db) integration. ACP sessions now: - Share the same DB as CLI and gateway sessions - Are searchable via session_search (FTS5) - Get token tracking, cost tracking, and session titles for free - Follow existing session pruning policies Key changes: - _get_db() lazily creates a SessionDB, resolving HERMES_HOME dynamically (not at import time) for test compatibility - _persist() creates session record + replaces messages in DB - _restore() loads from DB with source='acp' filter - cwd stored in model_config JSON field (no schema migration) - Model values coerced to str to handle mock agents in tests - Removed: json files, sessions_dir, ttl_days, _expire logic - Tests updated: DB-backed persistence, FTS search, tool_call round-tripping, source filtering