Fix towncrier fragment naming and CLAUDE.md instructions

Fragments in subdirectories should be named `<name>.md`, not
`<name>.<type>.md` - the type is already indicated by the directory.

- Rename feature/auto-deploy-docs.feature.md → feature/auto-deploy-docs.md
- Rename misc/+container-tag-no-confirm.misc.md → misc/+container-tag-no-confirm.md
- Update CLAUDE.md with correct fragment path format

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

docs/tutorials/ai-assistance-guide.md

@@ -54,10 +54,10 @@ EOF
 
 Add a fragment for user-visible changes:
 ```bash
-echo "Description" > docs/changelog.d/branch-name.feature.md
+echo "Description" > docs/changelog.d/feature/branch-name.md
 ```
 
-Types: `feature`, `bugfix`, `infra`, `doc`, `misc`
+Types (directory names): `feature`, `bugfix`, `infra`, `doc`, `misc`
 
 ## Service Locations