chore: refresh docs and adapt workflows for Gitea

.github/release-notes/v28.0.0.md

@@ -1,21 +1,18 @@
-FEATURES
+# v28.0.0
 
-- COMPATIBILITY
-    - Add a Gitea 28.0.0-aligned release of all 10 themes and 11 mail types per theme
+This release targets Gitea 28.0.0 and includes ten themes with eleven mail types each. For earlier Gitea versions, use the packages listed in the [compatibility matrix](https://gitea.kenanzhu.com/KenanZhu/GiteaMailTemplates/src/branch/main/COMPATIBILITY.md#compatibility-matrix).
 
-BUGFIXES
+## Fixes
 
-- THEMES (All 10)
-    - Replace the removed `FileSize` function with `FormatByteSize` in release-attachment emails, preventing Gitea 28.0.0 template rendering errors
-- PREVIEW AND TESTS
-    - Match the preview's file-size function to Gitea 28.0.0 and render release attachments in the example data
-    - Add an all-theme regression test for release attachments and the removed function
+- Replace the removed `FileSize` function with `FormatByteSize` in release-attachment emails across all ten themes.
+- Update the preview's file-size function for Gitea 28.0.0 and include release attachments in the example data.
+- Add an all-theme regression test for release attachments and the removed function.
 
-DOCS
+## Documentation
 
-- Update the English and Simplified Chinese READMEs and compatibility matrix for Gitea 28.0.0
-- Clarify that v28.0.0 requires Gitea 28.0.0; use v1.27.3 for Gitea 1.25.0–1.27.3
+- Update both READMEs and the compatibility matrix for Gitea 28.0.0.
+- Document the Gitea 28.0.0 requirement and direct users of earlier versions to the compatibility matrix.
 
----
+The snapshot-based source architecture now on `main` is separate, unreleased work. It is not included in the existing v28.0.0 archives.
 
-**Full Changelog:** [v1.27.3...v28.0.0](https://gitea.kenanzhu.com/KenanZhu/GiteaMailTemplates/compare/v1.27.3...v28.0.0)
+[Full changelog: v1.27.3…v28.0.0](https://gitea.kenanzhu.com/KenanZhu/GiteaMailTemplates/compare/v1.27.3...v28.0.0)