Add additional precompile output checks from issue #2081

Added checks for:
- Duplicate locale generation (react_on_rails:locale task)
- Duplicate webpack builds (via "Built at:" message count)
- ENOENT errors (missing files/directories)
- Deprecation warnings (logged as warning, not failure)

These patterns were explicitly requested in the updated issue description
to catch silent bugs that don't cause precompile to fail but indicate
problems like doubled build times or missing dependencies.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: justin808

.github/workflows/precompile-check.yml

@@ -170,7 +170,7 @@ jobs:
             fi
           fi
 
-          # Pattern 2: Duplicate task execution messages
+          # Pattern 2: Duplicate task execution messages (generate_packs)
           if grep -q "react_on_rails:generate_packs" precompile_output.txt; then
             GENERATE_PACKS_COUNT=$(grep -c "react_on_rails:generate_packs" precompile_output.txt || true)
             if [ "$GENERATE_PACKS_COUNT" -gt 1 ]; then
@@ -181,6 +181,26 @@ jobs:
             fi
           fi
 
+          # Pattern 2b: Duplicate locale generation
+          if grep -q "react_on_rails:locale" precompile_output.txt; then
+            LOCALE_COUNT=$(grep -c "react_on_rails:locale" precompile_output.txt || true)
+            if [ "$LOCALE_COUNT" -gt 1 ]; then
+              echo "::error::FAILURE: react_on_rails:locale task ran $LOCALE_COUNT times (should only run once)."
+              echo "  Matching lines:"
+              grep -n "react_on_rails:locale" precompile_output.txt
+              FAILURES_FOUND=1
+            fi
+          fi
+
+          # Pattern 2c: Duplicate webpack builds (check "Built at:" messages)
+          BUILT_AT_COUNT=$(grep -c "Built at:" precompile_output.txt || true)
+          if [ "$BUILT_AT_COUNT" -gt 1 ]; then
+            echo "::error::FAILURE: Detected $BUILT_AT_COUNT webpack builds (expected 1). Tasks may be running twice."
+            echo "  Matching lines:"
+            grep -n "Built at:" precompile_output.txt | head -5
+            FAILURES_FOUND=1
+          fi
+
           # Pattern 3: Module not found errors
           if grep -Ei "module not found|cannot find module|can't resolve" precompile_output.txt; then
             echo "::error::FAILURE: Module resolution errors detected in precompile output."
@@ -189,6 +209,14 @@ jobs:
             FAILURES_FOUND=1
           fi
 
+          # Pattern 3b: ENOENT errors (missing files/directories)
+          if grep -q "Error: ENOENT" precompile_output.txt; then
+            echo "::error::FAILURE: Missing file or directory errors detected."
+            echo "  Sample matching lines:"
+            grep -n "Error: ENOENT" precompile_output.txt | head -3
+            FAILURES_FOUND=1
+          fi
+
           # Pattern 4: Webpack build errors (use specific webpack error markers)
           if grep -Ei "webpack.*error|failed to compile|compilation failed|ERROR in" precompile_output.txt; then
             echo "::error::FAILURE: Webpack compilation errors detected."
@@ -229,6 +257,14 @@ jobs:
             grep -i "warning" precompile_output.txt | head -5
           fi
 
+          # Pattern 9: Deprecation warnings (log for visibility, don't fail)
+          DEPRECATION_COUNT=$(grep -c "DEPRECATION" precompile_output.txt || true)
+          if [ "$DEPRECATION_COUNT" -gt 0 ]; then
+            echo "::warning::Found $DEPRECATION_COUNT deprecation warnings. These may indicate future breakage."
+            echo "  Deprecation messages:"
+            grep -n "DEPRECATION" precompile_output.txt | head -5
+          fi
+
           if [ "$FAILURES_FOUND" -eq 1 ]; then
             echo ""
             echo "=========================================="