48be4674e9
/vibe (a full director/worker orchestration mode) had no user-facing documentation, and /fresh appeared only as a matrix row in the session-operations doc whose title already promised a "fresh" section. Neither was mentioned in the README. - Add docs/vibe-mode.md: enable/disable, fast/good worker tiers, the five vibe_* control tools, and the director workflow. - Add a "## Fresh" section to the session-operations doc describing the provider-stream/session-state reset and its contrast with /new and /drop. - Add a "Session controls" subsection to the README linking both docs. Fixes #6440