ci: rename to ci.yml and add lint-and-test gate

Rename lint-code.yml to ci.yml, add a `pull_request` trigger (required
checks must run on PRs), and add a `lint-and-test` aggregator job that
`needs: [build]`. The pylint job uses a matrix, which would otherwise
only produce per-version check contexts; the aggregator yields a single
`lint-and-test` context to satisfy the facioquo org ruleset.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: DaveSkender

.github/workflows/lint-code.yml .github/workflows/ci.yml.github/workflows/lint-code.yml renamed to .github/workflows/ci.yml

@@ -1,6 +1,8 @@
-name: Pylint
+name: CI
 
-on: [push]
+on:
+  push:
+  pull_request:
 
 jobs:
   build:
@@ -27,3 +29,14 @@ jobs:
     - name: Analysing the code with pylint
       run: |
         pylint $(git ls-files '*.py')
+
+  lint-and-test:
+    runs-on: ubuntu-latest
+    needs: [build]
+    if: always()
+    steps:
+      - name: Verify required jobs succeeded
+        if: ${{ contains(needs.*.result, 'failure') || contains(needs.*.result, 'cancelled') }}
+        run: |
+          echo "One or more required jobs did not succeed."
+          exit 1