feat(tags): Add tag archive route and admin interface integration

Implement Phase 3 of v1.3.0 tags feature per microformats-tags-design.md:

Routes (starpunk/routes/public.py):
- Add /tag/<tag> archive route with normalization and 404 handling
- Pre-load tags in index route for all notes
- Pre-load tags in note route for individual notes

Admin (starpunk/routes/admin.py):
- Parse comma-separated tag input in create route
- Parse tag input in update route
- Pre-load tags when displaying edit form
- Empty tag field removes all tags

Templates:
- Add tag input field to templates/admin/edit.html
- Add tag input field to templates/admin/new.html
- Use Jinja2 map filter to display existing tags

Implementation details:
- Tag URL parameter normalized to lowercase before lookup
- Tags pre-loaded using object.__setattr__ pattern (like media)
- parse_tag_input() handles trim, dedupe, normalization
- All existing tests pass (micropub categories, admin routes)

Per architect design:
- No pagination on tag archives (acceptable for v1.3.0)
- No autocomplete in admin (out of scope)
- Follows existing media loading patterns

Generated with Claude Code

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

docs/projectplan/v1.2.0/RELEASE.md

@@ -0,0 +1,21 @@
+# StarPunk v1.2.0 Release
+
+**Status**: Released 2025-12-09
+**Codename**: IndieWeb Features
+
+## Features
+
+- Media upload via Micropub
+- Caption/alt text support for images
+- Media display CSS fixes (responsive images)
+- Feed media support (Media RSS namespace, JSON Feed image field)
+
+## Bugs Addressed
+
+- Images too large on homepage
+- Captions displaying when should be alt text only
+- Images missing from feeds in feed readers
+
+## Implementation
+
+See `docs/design/v1.2.0/` for implementation details and reports.