feat: real release notes, restart button, reliable .run installer (0.0.10)

- feat(ci): set each Gitea release body from the matching CHANGELOG section
  (was hardcoded "Automated release for…")
- feat(updater): show "What's new" — release notes dialog before applying (GUI)
  and in `rigdoctor update` (CLI); fetch_latest/update_state now return notes
- feat(gui): "Restart now" button relaunches the app after an update is applied
- fix(packaging): build the self-extracting .run with a pure-Python extractor
  (packaging/make_run.py) instead of makeself, so it attaches to every release
  (it was silently skipped before)
- chore: adopt Conventional Commits + git-cliff (cliff.toml, packaging/
  changelog.sh) for changelog generation going forward (D20)
- chore(gui): drop internal module refs (M4, M5, …) from Setup descriptions

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

docs/DECISIONS.md

@@ -191,12 +191,24 @@ desirable — access control is delegated to Gitea.
 PATCH for ordinary changes, MINOR for larger milestones). `__version__`
 (`rigdoctor/__init__.py`) and `pyproject.toml` are the single source of truth and **must match
 the git release tag** so the auto-updater (D18) can compare versions. Every change updates
-`CHANGELOG.md` (Keep a Changelog style). *Note:* an early placeholder `0.1.0` was corrected to
+`CHANGELOG.md` — now generated from **Conventional Commits** via git-cliff (see D20). *Note:* an early placeholder `0.1.0` was corrected to
 follow the released **0.0.x** line — first release was **V0.0.1**; current is **0.0.2**.
 
+### D20 — Automated changelog & release notes — *DECIDED 2026-05-21*
+**Release notes are generated from our changes, surfaced in the auto-updater.**
+- *Release body:* CI sets each Gitea release's `body` from the matching `CHANGELOG.md`
+  section (was a hardcoded "Automated release for…"). The updater fetches the release `body`
+  and shows **"What's new"** — a dialog before applying (GUI) and in `rigdoctor update` (CLI).
+- *Generation:* adopt **Conventional Commits** (`feat:`/`fix:`/`docs:`/`chore:` …) and
+  **git-cliff** (`cliff.toml`, `packaging/changelog.sh`) to generate `CHANGELOG.md` from
+  commit history. Refines D19's "hand-write CHANGELOG" to "generate it from conventional
+  commits"; `__version__`/`pyproject.toml`/tag still the source of truth for the version.
+- *CI does not auto-commit the changelog* (avoids push loops) — it's regenerated by the dev
+  via the script when cutting a version; CI only reads the section for the release body.
+
 ## Open
 
-None currently — all tracked decisions (D1–D19) are resolved. New questions will be added
+None currently — all tracked decisions (D1–D20) are resolved. New questions will be added
 here as they arise. Remaining detail to flesh out during build: the tray's supporting-action
 set (D13), per-module apt package names, M12's tunnel/token specifics, and M13's
 update mechanism (APT repo vs. self-installed `.deb`).