Fix misc changelog type to show content

The showcontent=false setting expected issue-number-style fragment names.
Since blumeops uses branch names for fragments, change to showcontent=true
so the content is displayed like other fragment types.

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

docs/changelog.d/fix-quartz-git-dates.doc.md

@@ -0,0 +1 @@
+Fix misc changelog fragment type to show content (was showing empty entries)

docs/how-to/update-documentation.md

@@ -56,7 +56,7 @@ Fragments are automatically collected into `CHANGELOG.md` (at repo root) during
 | `bugfix` | `bugfix/` | Bug fixes |
 | `infra` | `infra/` | Infrastructure changes |
 | `doc` | `doc/` | Documentation updates |
-| `misc` | `misc/` | Other (content hidden in changelog) |
+| `misc` | `misc/` | Other changes |
 
 ## Runner Environment
 

towncrier.toml

@@ -37,4 +37,4 @@ showcontent = true
 [[tool.towncrier.type]]
 directory = "misc"
 name = "Miscellaneous"
-showcontent = false
+showcontent = true