Change release workflow to trigger on release creation

Replaced tag-push trigger with on: release: types: [created] to match
the riddl project pattern. Added workflow_dispatch for manual triggering
with a tag input. Release artifact upload now uses gh release upload
with --clobber instead of creating a new release.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: reid-spencer

.github/workflows/release.yml

@@ -1,9 +1,13 @@
 name: Release
 
 on:
-  push:
-    tags:
-      - '[0-9]*'
+  release:
+    types: [created]
+  workflow_dispatch:
+    inputs:
+      tag:
+        description: 'Release tag to build for (e.g., 1.3.4)'
+        required: true
 
 permissions:
   contents: write
@@ -20,6 +24,7 @@ jobs:
       - name: Checkout Source Code
         uses: actions/checkout@v4
         with:
+          ref: ${{ github.event.release.tag_name || github.event.inputs.tag }}
           fetch-depth: 0
 
       - name: Setup JDK 25
@@ -43,14 +48,12 @@ jobs:
           cp target/scala-2.12/sbt-1.0/sbt-ossuminc-*.jar staging/
           ls -la staging/
 
-      - name: Create GitHub Release
+      - name: Upload Artifacts to Release
         env:
           GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         run: |
-          gh release create "${{ github.ref_name }}" \
-            --title "v${{ github.ref_name }}" \
-            --generate-notes \
-            staging/*.jar
+          TAG="${{ github.event.release.tag_name || github.event.inputs.tag }}"
+          gh release upload "$TAG" staging/*.jar --clobber
 
       - name: Cleanup Before Caching
         shell: bash