add manual knob

Author: NickKhalow

.github/workflows/build-unitycloud.yml

@@ -78,6 +78,15 @@ on:
         required: false
         default: false
         type: boolean
+      platforms:
+        description: 'Which platforms to build'
+        required: true
+        default: 'both'
+        type: choice
+        options:
+          - both
+          - windows-only
+          - macos-only
   workflow_call:
     inputs:
       profile:
@@ -423,27 +432,45 @@ jobs:
         run: |
           set -euo pipefail
 
-          labels="${{ join(github.event.pull_request.labels.*.name, ' ') }}"
-          echo "Labels: '$labels'"
-
-          has_windows_only=false
-          has_macos_only=false
-          if echo "$labels" | grep -qw 'windows-only'; then has_windows_only=true; fi
-          if echo "$labels" | grep -qw 'macos-only'; then has_macos_only=true; fi
+          # platform_build_mode: windows | macos | both
+          platform_build_mode=both
 
-          if [ "$has_windows_only" = "true" ] && [ "$has_macos_only" = "true" ]; then
-            echo "::error::Both 'windows-only' and 'macos-only' labels are applied. Remove one — they are mutually exclusive."
-            exit 1
-          fi
+          dispatch_platforms="${{ github.event.inputs.platforms }}"
+          echo "Dispatch platforms: '$dispatch_platforms'"
 
-          if [ "$has_windows_only" = "true" ]; then
-            targets='["windows64"]'
-          elif [ "$has_macos_only" = "true" ]; then
-            targets='["macos"]'
+          if [ "$dispatch_platforms" = "windows-only" ]; then
+            platform_build_mode=windows
+          elif [ "$dispatch_platforms" = "macos-only" ]; then
+            platform_build_mode=macos
           else
-            targets='["windows64","macos"]'
+            labels="${{ join(github.event.pull_request.labels.*.name, ' ') }}"
+            echo "Labels: '$labels'"
+
+            label_match_count=0
+            if echo "$labels" | grep -qw 'windows-only'; then
+              platform_build_mode=windows
+              label_match_count=$((label_match_count + 1))
+            fi
+            if echo "$labels" | grep -qw 'macos-only'; then
+              platform_build_mode=macos
+              label_match_count=$((label_match_count + 1))
+            fi
+
+            if [ "$label_match_count" -gt 1 ]; then
+              echo "::error::Both 'windows-only' and 'macos-only' labels are applied. Remove one — they are mutually exclusive."
+              exit 1
+            fi
           fi
 
+          echo "Platform build mode: $platform_build_mode"
+
+          case "$platform_build_mode" in
+            windows) targets='["windows64"]' ;;
+            macos)   targets='["macos"]' ;;
+            both)    targets='["windows64","macos"]' ;;
+            *) echo "::error::Unknown platform_build_mode '$platform_build_mode'"; exit 1 ;;
+          esac
+
           echo "Targets: $targets"
           echo "targets=$targets" >> "$GITHUB_OUTPUT"