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
 

docs/tutorials/contributing.md

@@ -95,15 +95,15 @@ Depending on what you're changing:
 
 For user-visible changes:
 ```bash
-echo "Description of your change" > docs/changelog.d/your-branch.feature.md
+echo "Description of your change" > docs/changelog.d/feature/your-branch.md
 ```
 
-Fragment types:
-- `.feature.md` - New functionality
-- `.bugfix.md` - Bug fixes
-- `.infra.md` - Infrastructure changes
-- `.doc.md` - Documentation
-- `.misc.md` - Other
+Fragment types (use as directory name):
+- `feature/` - New functionality
+- `bugfix/` - Bug fixes
+- `infra/` - Infrastructure changes
+- `doc/` - Documentation
+- `misc/` - Other
 
 ### 4. Test Your Changes