chore: Overhaul deploy workflow to push to LuaRocks and GHCR

.github/workflows/deploy.yml

@@ -1,16 +1,44 @@
 name: Deploy
 
-on:
-  push:
-    branches:
-      - master
-    tags:
-      - latest
-      - v*
+on: [ push, workflow_dispatch ]
 
 jobs:
 
+  affected:
+    uses: sile-typesetter/.github/.github/workflows/list_affected_rockspecs.yml@master
+
+  build:
+    needs: affected
+    if: ${{ needs.affected.outputs.rockspecs }}
+    uses: sile-typesetter/.github/.github/workflows/test_build_rock.yml@master
+    with:
+      rockspecs: ${{ needs.affected.outputs.rockspecs }}
+
+  upload:
+    needs: [ affected, build ]
+    # Only run upload if:
+    # 1. We are on the canonical repository (no uploads from forks)
+    # 2. The current commit is either tagged or on the default branch (the workflow will upload dev/scm rockspecs any
+    #    time they are touched, tagged ones whenever the edited rockspec and tag match)
+    # 3. Some rockspecs were changed — this implies the commit changing the rockspec is the same one that gets tagged
+    if: >-
+      ${{
+        github.repository == 'sile-typesetter/fontproof' &&
+        ( github.ref_name == 'master' || startsWith(github.ref, 'refs/tags/') ) &&
+        needs.affected.outputs.rockspecs
+      }}
+    uses: sile-typesetter/.github/.github/workflows/upload_to_luarocks.yml@master
+    with:
+      rockspecs: ${{ needs.affected.outputs.rockspecs }}
+    secrets:
+      apikey: ${{ secrets.LUAROCKS_SILETYPESETTER }}
+
   ghcr:
+    if: >-
+      ${{
+        github.repository == 'sile-typesetter/fontproof' &&
+        ( github.ref_name == 'master' || startsWith(github.ref, 'refs/tags/') )
+      }}
     strategy:
       fail-fast: false
     runs-on: ubuntu-22.04