* feat: add two-phase startup lifecycle
Allow the dashboard to become available before plugin bootstrap completes and surface runtime readiness and failure states to API callers.
Guard plugin-facing endpoints until runtime is ready and clean up provider and plugin runtime state safely across bootstrap failures, retries, stop, and restart flows.
* fix: harden runtime cleanup review fixes
Continue terminating remaining providers and disable MCP servers even if one provider terminate hook fails.
Also add InitialLoader failure-path coverage and extract guarded plugin routes into a shared constant for easier review and maintenance.
* fix: harden deferred startup recovery
* fix: streamline runtime guard handling
* fix: simplify runtime lifecycle coordination
* fix: restore orchestrator logger binding