fix: correct tojson|safe usage in templates and update validator

- Remove |safe from |tojson in HTML attributes (x-data) - quotes must
  become " for browsers to parse correctly
- Update LANG-002 and LANG-003 architecture rules to document correct
  |tojson usage patterns:
  - HTML attributes: |tojson (no |safe)
  - Script blocks: |tojson|safe
- Fix validator to warn when |tojson|safe is used in x-data (breaks
  HTML attribute parsing)
- Improve code quality across services, APIs, and tests

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

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

scripts/validators/base.py

@@ -56,7 +56,7 @@ class FileResult:
     def status(self) -> str:
         if self.errors > 0:
             return "FAILED"
-        elif self.warnings > 0:
+        if self.warnings > 0:
             return "PASSED*"
         return "PASSED"
 
@@ -64,7 +64,7 @@ class FileResult:
     def status_icon(self) -> str:
         if self.errors > 0:
             return "❌"
-        elif self.warnings > 0:
+        if self.warnings > 0:
             return "⚠️"
         return "✅"
 
@@ -220,17 +220,19 @@ class BaseValidator:
                 # Look for the function definition
                 for j in range(i + 1, min(i + 10, len(lines))):
                     next_line = lines[j].strip()
-                    if next_line.startswith("def ") or next_line.startswith("async def "):
+                    if next_line.startswith("def ") or next_line.startswith(
+                        "async def "
+                    ):
                         # Extract function name
                         match = re.search(r"(?:async\s+)?def\s+(\w+)", next_line)
                         if match:
                             func_name = match.group(1)
                             results.append((i + 1, decorator, func_name))
                         break
-                    elif next_line.startswith("@"):
+                    if next_line.startswith("@"):
                         # Multiple decorators - continue to next
                         continue
-                    elif next_line and not next_line.startswith("#"):
+                    if next_line and not next_line.startswith("#"):
                         # Non-decorator, non-comment line - stop looking
                         break
             i += 1
@@ -303,7 +305,7 @@ class BaseValidator:
         Returns (is_valid, error_message) tuple.
         """
         try:
-            with open(file_path, "r", encoding="utf-8") as f:
+            with open(file_path, encoding="utf-8") as f:
                 json.load(f)
             return True, ""
         except json.JSONDecodeError as e: