fix: use table_header_custom for custom headers in subscription pages

The table_header() macro doesn't support caller() - it takes a columns list.
Using {% call table_header() %} caused a Jinja2 error:
  "macro 'table_header' was invoked with two values for the special caller argument"

Changes:
- Add table_header_custom() macro that supports caller() for custom headers
- Update subscriptions.html, subscription-tiers.html, billing-history.html
- Add TPL-008 architecture rule to detect this pattern
- Renumber TPL-009 (block names) and TPL-010 (Alpine vars)

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

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

scripts/validate_architecture.py

@@ -813,7 +813,10 @@ class ArchitectureValidator:
             # TPL-007: Check empty state implementation
             self._check_template_empty_state(file_path, content, lines)
 
-            # TPL-008: Check for invalid block names
+            # TPL-008: Check for call table_header() pattern (should be table_header_custom)
+            self._check_table_header_call_pattern(file_path, content, lines)
+
+            # TPL-009: Check for invalid block names
             if is_admin:
                 self._check_valid_block_names(file_path, content, lines)
 
@@ -1058,11 +1061,41 @@ class ArchitectureValidator:
                 suggestion='Add <template x-if="items.length === 0">No items found</template>',
             )
 
+    def _check_table_header_call_pattern(
+        self, file_path: Path, content: str, lines: list[str]
+    ):
+        """TPL-008: Check that {% call table_header() %} is not used.
+
+        The table_header() macro doesn't support caller() - it takes a columns list.
+        Using {% call table_header() %} causes a Jinja2 error:
+            "macro 'table_header' was invoked with two values for the special caller argument"
+
+        Use table_header_custom() instead for custom headers with caller().
+        """
+        if "noqa: tpl-008" in content.lower():
+            return
+
+        import re
+        pattern = re.compile(r"{%\s*call\s+table_header\s*\(\s*\)\s*%}")
+
+        for i, line in enumerate(lines, 1):
+            if pattern.search(line):
+                self._add_violation(
+                    rule_id="TPL-008",
+                    rule_name="Use table_header_custom for custom headers",
+                    severity=Severity.ERROR,
+                    file_path=file_path,
+                    line_number=i,
+                    message="{% call table_header() %} causes Jinja2 error - table_header doesn't support caller()",
+                    context=line.strip()[:80],
+                    suggestion="Use {% call table_header_custom() %} for custom headers with th_sortable or custom <th> elements",
+                )
+
     def _check_valid_block_names(
         self, file_path: Path, content: str, lines: list[str]
     ):
-        """TPL-008: Check that templates use valid block names from base template"""
-        if "noqa: tpl-008" in content.lower():
+        """TPL-009: Check that templates use valid block names from base template"""
+        if "noqa: tpl-009" in content.lower():
             return
 
         # Skip base templates
@@ -1092,7 +1125,7 @@ class ArchitectureValidator:
                 block_name = match.group(1)
                 if block_name in invalid_blocks:
                     self._add_violation(
-                        rule_id="TPL-008",
+                        rule_id="TPL-009",
                         rule_name="Use valid block names from base templates",
                         severity=Severity.ERROR,
                         file_path=file_path,
@@ -1105,8 +1138,8 @@ class ArchitectureValidator:
     def _check_alpine_template_vars(
         self, file_path: Path, content: str, lines: list[str], js_content: str
     ):
-        """TPL-009: Check that Alpine variables used in templates are defined in JS"""
-        if "noqa: tpl-009" in content.lower():
+        """TPL-010: Check that Alpine variables used in templates are defined in JS"""
+        if "noqa: tpl-010" in content.lower():
             return
 
         import re
@@ -1141,7 +1174,7 @@ class ArchitectureValidator:
                 for i, line in enumerate(lines, 1):
                     if var in line and ("error_state" in line or "action_dropdown" in line):
                         self._add_violation(
-                            rule_id="TPL-009",
+                            rule_id="TPL-010",
                             rule_name="Alpine variables must be defined in JS component",
                             severity=Severity.ERROR,
                             file_path=file_path,
@@ -2913,11 +2946,14 @@ class ArchitectureValidator:
             if not is_base_or_partial and not is_macro and not is_components_page:
                 self._check_number_stepper_macro_usage(file_path, content, lines)
 
-            # TPL-008: Check for invalid block names
+            # TPL-008: Check for call table_header() pattern
+            self._check_table_header_call_pattern(file_path, content, lines)
+
+            # TPL-009: Check for invalid block names
             if not is_base_or_partial:
                 self._check_valid_block_names(file_path, content, lines)
 
-            # TPL-009: Check Alpine variables are defined in JS
+            # TPL-010: Check Alpine variables are defined in JS
             if not is_base_or_partial and not is_macro and not is_components_page:
                 # Try to find corresponding JS file
                 # Template: app/templates/admin/messages.html -> JS: static/admin/js/messages.js