tasks(using-yt-tools): close install + hermes-mapping [🟢🟢]

- using-yt-tools-install: ffmpeg 8.1.1 on PATH, venv populated,
  yt-tools 0.1.0 editable, 4 CLIs respond, 67/67 unit tests pass
  on this Windows host.
- using-yt-tools-hermes-mapping: registered as `pending` with
  intended:{mode:auto, category:research}; build-hermes.py emits
  26 skills (1 pending) and SKIPPED.md lists the entry. Promotion
  to `auto` gated on using-yt-tools-test-trigger 🟢.

NB: triggers/url_pattern from the task block's yaml sketch don't
match the mapping schema — they live in SKILL.md description and
Hermes picks them up automatically. Build script only consumes
mode/category/reason/intended/replace-rules.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

dist-hermes/SKIPPED.md

@@ -17,4 +17,4 @@ Do not edit by hand — edit the mapping and re-run the build.
 
 ## Pending (deferred to follow-up tasks)
 
-(none)
+- **using-yt-tools** — Shells out to yt-dlp + ffmpeg and writes ./yt-cache/ in cwd. Behavioral audit via using-yt-tools-test-trigger required before promotion to auto. → intended: `mode: auto, category: research`