ci: run the heavy Gradle jobs on the self-hosted runners

Requires the Android SDK in the runner image. Also gates the disk-cleanup
step to hosted runners, where it would otherwise strip the host.

.github/workflows/quality.yml

@@ -24,6 +24,9 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Free Disk Space (Ubuntu)
+        # Only meaningful on GitHub's throwaway VMs. On a persistent self-hosted runner this
+        # would delete dotnet/haskell/docker images from the host on every run.
+        if: runner.environment == 'github-hosted'
         uses: jlumbroso/free-disk-space@54081f138730dfa15788a46383842cd2f914a1be
         with:
           # This might remove tools that are actually needed, if set to "true" but frees about 6 GB
@@ -67,7 +70,7 @@ jobs:
 
   checkDependencies:
     name: Search for invalid dependencies
-    runs-on: ubuntu-latest
+    runs-on: [self-hosted, Linux, X64]
     steps:
       - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
         with:
@@ -91,7 +94,7 @@ jobs:
   # Code checks
   konsist:
     name: Konsist tests
-    runs-on: ubuntu-latest
+    runs-on: [self-hosted, Linux, X64]
     # Allow all jobs on main and develop. Just one per PR.
     concurrency:
       group: ${{ github.ref == 'refs/heads/main' && format('check-konsist-main-{0}', github.sha) || github.ref == 'refs/heads/develop' && format('check-konsist-develop-{0}', github.sha) || format('check-konsist-{0}', github.ref) }}
@@ -132,7 +135,7 @@ jobs:
 
   compose:
     name: Compose tests
-    runs-on: ubuntu-latest
+    runs-on: [self-hosted, Linux, X64]
     # Allow all jobs on main and develop. Just one per PR.
     concurrency:
       group: ${{ github.ref == 'refs/heads/main' && format('check-compose-main-{0}', github.sha) || github.ref == 'refs/heads/develop' && format('check-compose-develop-{0}', github.sha) || format('check-compose-{0}', github.ref) }}
@@ -166,7 +169,7 @@ jobs:
 
   lint:
     name: Android lint check
-    runs-on: ubuntu-latest
+    runs-on: [self-hosted, Linux, X64]
     # Allow all jobs on main and develop. Just one per PR.
     concurrency:
       group: ${{ github.ref == 'refs/heads/main' && format('check-lint-main-{0}', github.sha) || github.ref == 'refs/heads/develop' && format('check-lint-develop-{0}', github.sha) || format('check-lint-{0}', github.ref) }}
@@ -211,7 +214,7 @@ jobs:
 
   detekt:
     name: Detekt checks
-    runs-on: ubuntu-latest
+    runs-on: [self-hosted, Linux, X64]
     # Allow all jobs on main and develop. Just one per PR.
     concurrency:
       group: ${{ github.ref == 'refs/heads/main' && format('check-detekt-main-{0}', github.sha) || github.ref == 'refs/heads/develop' && format('check-detekt-develop-{0}', github.sha) || format('check-detekt-{0}', github.ref) }}
@@ -252,7 +255,7 @@ jobs:
 
   ktlint:
     name: Ktlint checks
-    runs-on: ubuntu-latest
+    runs-on: [self-hosted, Linux, X64]
     # Allow all jobs on main and develop. Just one per PR.
     concurrency:
       group: ${{ github.ref == 'refs/heads/main' && format('check-ktlint-main-{0}', github.sha) || github.ref == 'refs/heads/develop' && format('check-ktlint-develop-{0}', github.sha) || format('check-ktlint-{0}', github.ref) }}