CI: replace actions with plain run steps (no github deps)

.gitea/workflows/ci.yml

@@ -4,40 +4,24 @@ on:
   pull_request:
   push:
     branches: [main]
+  workflow_dispatch:
 
 jobs:
   lint:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
-      - uses: actions/setup-python@v5
-        with:
-          python-version: "3.12"
-          cache: pip
-      - run: pip install -r requirements.txt
-      - run: ruff check .
+      - run: ls -la "$GITEA_WORKSPACE" && pip install ruff==6.* && (cd "$GITEA_WORKSPACE" && ruff check .)
 
   test:
     needs: lint
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
-      - uses: actions/setup-python@v5
-        with:
-          python-version: "3.12"
-          cache: pip
-      - run: pip install -r requirements.txt
-      - run: pytest -q --cov=app --cov-branch --cov-fail-under=60
+      - run: pip install -r "$GITEA_WORKSPACE/requirements.txt" pytest pytest-cov
+      - run: cd "$GITEA_WORKSPACE" && pytest -q --cov=app --cov-branch --cov-fail-under=60
 
   metrics:
     needs: test
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
-      - uses: actions/setup-python@v5
-        with:
-          python-version: "3.12"
-          cache: pip
-      - run: pip install -r requirements.txt
-      - run: radon cc app -s -a
-      - run: xenon --max-absolute C app/
+      - run: pip install radon xenon
+      - run: cd "$GITEA_WORKSPACE" && radon cc app -s -a && xenon --max-absolute C app/