#727 Test

Summary by cubic

Headless chat runs now install global skills into the sandbox before discovery, so agents get the skill tool instead of guessing endpoints. This fixes empty-skill sandboxes in POST /api/chat/runs.

• Bug Fixes
  • In provisionRunSession, call installSessionGlobalSkills right after connect and before discoverSkills; continue even if install fails (best-effort).
  • Added tests to assert install happens before discovery and that runs proceed when install errors.