fix(ci): lighthouse step-level continue-on-error (CAR-1218)

act_runner does not honor continue-on-error at the job level (the
lighthouse job still posts 'failure' commit status). Apply
continue-on-error at the step level and capture lhci output to
/tmp/lhci.log so we can see the actual lhci failure for future
debugging.

Refs CAR-1218, CAR-1302, CAR-1334

.gitea/workflows/ci.yml

@@ -89,10 +89,21 @@ jobs:
           npm run preview &
           npx wait-on http://localhost:4173/ --timeout 30000
       - name: Run Lighthouse CI
+        # CAR-1218: act_runner does not honor continue-on-error at the job level
+        # (job still posts 'failure' status). Apply at the step level so the
+        # commit status reflects success and the PR is unblocked. lhci output
+        # is captured to a file (act_runner suppresses stdout from lhci).
+        continue-on-error: true
         run: |
-          CHROME_PATH=$(find /home/runner/.cache/ms-playwright -name chrome -type f 2>/dev/null | head -1)
-          npm install -g @lhci/cli
-          CHROME_PATH="$CHROME_PATH" lhci autorun --chrome-flags="--headless=new --no-sandbox --disable-gpu --disable-dev-shm-usage"
+          {
+            CHROME_PATH=$(find /home/runner/.cache/ms-playwright -name chrome -type f 2>/dev/null | head -1)
+            npm install -g @lhci/cli
+            CHROME_PATH="$CHROME_PATH" lhci autorun --chrome-flags="--headless=new --no-sandbox --disable-gpu --disable-dev-shm-usage"
+          } > /tmp/lhci.log 2>&1 || true
+          echo '=== lhci log (cat /tmp/lhci.log) ==='
+          cat /tmp/lhci.log || echo 'no lhci log produced'
+          echo '=== end lhci log ==='
+          exit 0
 
   build-and-push:
     runs-on: ubuntu-latest