feat: add drilldown link icon indicator to agent dashboard cards

fix: resolve tool error counting logic and add advanced UI execution metrics

feat(agents): full implementation of harness engineering and file sync fixes ...

- Implemented Area 1: Backend scaffolding, CRUD, schemas, and session locking
- Implemented Area 2: Agent execution loop, RAG integration, and Circuit Breaker
- Updated UI: Configure CRON triggers, Target Mesh nodes, and display system prompt in Agent Drilldown
- Fixed LLM fallback resolving vertex_ai_beta
- Fixed File System Sync pseudo-nodes (hub, local) raising 'Offline'
- Fixed FileSystemNavigator initialPath bug causing synced files not to render in UI Mesh Workspace

fix(tool_service): fix LazyFileContent property indentation bug causing NoneType error

fix(frontend): corrected mesh node field mapping in AgentDrillDown ...

The Target Mesh Node dropdown was incorrectly using 'id', 'name', and 'status' instead of the backend's 'node_id', 'display_name', and 'last_status', causing nodes to appear as '(unknown)'.

fix(llm): eradicate gemini-1.5-flash 404 from production ...

- Implemented substring normalization for Gemini models in config.py
- Forced redirection of 1.5-flash to 2.5-flash in RAG service
- Fixed model name resolution in provider factory to handle suffixed names
- Normalized health checks to use 2.5-flash baseline
- Removed hardcoded 1.5-flash defaults from STT/TTS providers and agent loop

Fix frontend build crash by updating getNodes to getUserAccessibleNodes and restore production service sync