fix(release): Add semver fields to changelog categories (#1193)

This enables Craft's automatic version bump detection for changelog preview
comments on PRs. Without these fields, the changelog preview shows 'None'
for the semver impact even when PRs match categories like Features or Bug Fixes.

The semver mappings follow conventional commit semantics:
- Important Changes: minor
- Breaking Changes: major
- Features: minor
- Bug Fixes: patch
- Documentation: patch
- Internal Changes: patch

Author: BYK

.github/release.yml

@@ -5,34 +5,40 @@ changelog:
   categories:
     - title: Important Changes
       labels:
-        - "Changelog: Important Change"
+        - 'Changelog: Important Change'
+      semver: minor
     - title: Breaking Changes
       labels:
-        - "Changelog: Breaking Change"
+        - 'Changelog: Breaking Change'
       commit_patterns:
         - "^(?<type>\\w+(?:\\((?<scope>[^)]+)\\))?!:\\s*)"
-    
+      semver: major
+
     - title: Features
       labels:
-        - "Changelog: Feature"
+        - 'Changelog: Feature'
       commit_patterns:
         - "^(?<type>feat(?:\\((?<scope>[^)]+)\\))?!?:\\s*)"
-    
+      semver: minor
+
     - title: Bug Fixes
       labels:
-        - "Changelog: Bugfix"
+        - 'Changelog: Bugfix'
       commit_patterns:
         - "^(?<type>fix(?:\\((?<scope>[^)]+)\\))?!?:\\s*)"
-        - "^Revert \""
-    
+        - '^Revert "'
+      semver: patch
+
     - title: Documentation
       labels:
-        - "Changelog: Docs"
+        - 'Changelog: Docs'
       commit_patterns:
         - "^(?<type>docs?(?:\\((?<scope>[^)]+)\\))?!?:\\s*)"
-  
+      semver: patch
+
     - title: Internal Changes
       labels:
-        - "Changelog: Internal"
+        - 'Changelog: Internal'
       commit_patterns:
-        - "^(?<type>(?:build|refactor|meta|chore|ci|ref|perf)(?:\\((?<scope>[^)]+)\\))?!?:\\s*)"
+        - "^(?<type>(?:build|refactor|meta|chore|ci|ref|perf)(?:\\((?<scope>[^)]+)\\))?!?:\\s*)"
+      semver: patch