Adds CHANGELOG.md entries for the 3.47.9 stable hotfix (#195073, #194959, #195015). CI-only cherry-picks are omitted.
Tracker: #195427
### Edits to cherry-pick changelog descriptions
- #195073 and #195015: used verbatim from the cherry-pick PR's "Changelog Description".
- #194959 (@bkonyi): **edited** to follow [Hotfix Documentation Best Practices](https://github.com/flutter/flutter/blob/main/docs/releases/Hotfix-Documentation-Best-Practices.md) (describe the state prior to the fix):
- Original: "When running `flutter test` in pub workspaces, monorepos, or symlinked directories, fix a StateError crash during native assets compilation by falling back to appName matching."
- Changelog: "When running `flutter test` in pub workspaces, monorepos, or symlinked directories on any platform, native assets compilation crashed with a `StateError`."
- Changes: rewrote as the pre-fix behavior, added "on any platform", dropped the implementation detail ("falling back to appName matching").
@bkonyi FYI — please let us know if the edited wording for #194959 looks right.