Reuse the shared dependency-aware plugin loader for Core hot reloads. Scope watcher setup callbacks and subscriptions, recover missing external helpers, and preserve explicit local entrypoint invalidation without reloading package dependencies. Add regression coverage and portable RPC fixtures.
- V2 tool execute hooks: add `ctx.tool.execute.before/after` plugin API,
core ToolHooks service, and registry wiring so hosted/local tool calls
run registered before/after hooks; provider-executed calls are excluded.
- Session synthetic endpoint: add `POST /api/session/:sessionID/synthetic`
with text/description/metadata plus regenerated Promise/Effect/JS client
surfaces.
- SessionInstructions service: read tool discovers nearby AGENTS.md walking
up to the Location root (exclusive) and injects them as durable synthetic
instructions, with lazy history dedup of prior claims.
- to-llm-message: stop forwarding synthetic message metadata to the model so
bookkeeping annotations stay model-hidden.
- schema changelog entry for synthetic metadata and the metadata leak fix.