- Added process-wide singleton instances for InternalUrlRouter, AsyncJobManager, and MCPManager.
- Changed internal URL protocols to resolve through registered sessions and scan all active roots/datasets for matches.
- Refactored agent, artifact, memory, rule, skill, jobs, and mcp handlers to use shared manager and rule/skill state.
- Removed per-session protocol/tool wiring and switched tests to initialize and reset global singleton state.
- Added immutable metadata to protocol handlers and had the router copy each handler's setting onto resolved internal resources.
- Updated read and search tools to honor `resource.immutable`, and made search suppress hashline anchors only for immutable source paths while preserving them for mutable files.
- Expanded internal URL tests to cover mutable local resources and mixed immutable/mutable search input hashline behavior.
can1357