fix(ci): untrack playwright-report artifact and close gitignore/CI guard gaps

.gitattributes

@@ -0,0 +1,2 @@
+# Ensure shell scripts always use LF line endings regardless of OS
+*.sh text eol=lf

.gitignore

@@ -102,4 +102,9 @@ backend/__pycache__/
 Thumbs.db
 
 backend/data/reports/*
-!backend/data/reports/.gitkeep
+!backend/data/reports/.gitkeep
+
+# Frontend generated test artifacts (see CONTRIBUTING.md)
+frontend/playwright-report/
+frontend/test-results/
+frontend/.vite/

scripts/check-artifacts.sh

@@ -9,22 +9,51 @@ BLOCKED_PATTERNS=(
   "frontend/node_modules/"
   ".vite/deps/"
 )
-echo "Checking for generated frontend artifacts..."
+
+# ── Check 1: files already tracked in git history ─────────────────────────────
+# The diff-only check below cannot catch artifacts already committed to the base
+# branch. This check catches those.
+echo "Checking for tracked generated artifacts in git history..."
+TRACKED_FOUND=()
+for pattern in "${BLOCKED_PATTERNS[@]}"; do
+  while IFS= read -r match; do
+    TRACKED_FOUND+=("$match")
+  done < <(git ls-files "${pattern}" 2>/dev/null || true)
+done
+
+if [[ ${#TRACKED_FOUND[@]} -gt 0 ]]; then
+  echo "ERROR: Generated artifact is tracked by git and must be removed:"
+  for f in "${TRACKED_FOUND[@]}"; do echo "  - $f"; done
+  echo ""
+  echo "Fix:"
+  echo "  git rm --cached <file>"
+  echo "  Add the path to .gitignore"
+  echo "  See CONTRIBUTING.md for details."
+  exit 1
+fi
+
+# ── Check 2: files newly added in this PR/branch ──────────────────────────────
+echo "Checking for generated artifacts in PR diff..."
 if git rev-parse --verify "${BASE_BRANCH}" >/dev/null 2>&1; then
   CHANGED_FILES=$(git diff --name-only "${BASE_BRANCH}"...HEAD 2>/dev/null || git diff --name-only HEAD)
 else
   CHANGED_FILES=$(git diff --name-only --cached)
 fi
+
 FOUND=()
 for pattern in "${BLOCKED_PATTERNS[@]}"; do
-  while IFS= read -r match; do FOUND+=("$match")
+  while IFS= read -r match; do
+    FOUND+=("$match")
   done < <(echo "$CHANGED_FILES" | grep -E "^${pattern}" 2>/dev/null || true)
 done
+
 if [[ ${#FOUND[@]} -gt 0 ]]; then
-  echo "ERROR: Artifact files found:"
+  echo "ERROR: Artifact files found in this branch:"
   for f in "${FOUND[@]}"; do echo "  - $f"; done
+  echo ""
   echo "Fix: git rm --cached <file>"
   exit 1
 fi
+
 echo "All clear!"
 exit 0