feat(arch-rules): TPL-016 flags large persona templates that skip shared/

Architecture rule that warns on any template under
app/modules/<m>/templates/<m>/{admin,merchant,store}/*.html that
exceeds 75 LOC AND does not {% include %} a `*/shared/*` partial.

Catches new persona-specific templates that inline body content rather
than sharing it with sibling personas (the project-wide pain point that
prompted the persona-template-consolidation work).

- Rule definition in .architecture-rules/frontend.yaml at warning
  severity. Suppressible per-file with `{# noqa: TPL-016 #}`.
- Check function `_check_persona_template_shared_include` in
  scripts/validate/validate_architecture.py, wired at both template
  validation sites (full scan + per-file -f mode).
- Loyalty was migrated under this rule and reports clean (5 legit
  exceptions carry noqa with reason).
- First run surfaces ~110 warnings across other modules — the
  migration backlog. Severity stays at warning until at least one
  non-loyalty module is migrated, then escalate to error.

See docs/architecture/persona-template-consolidation.md for the
pattern this rule guards.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

.architecture-rules/frontend.yaml

@@ -644,6 +644,37 @@ template_rules:
       exceptions:
         - "shared/macros/headers.html"
 
+  - id: "TPL-016"
+    name: "Persona templates >75 LOC must include a shared/ partial"
+    severity: "warning"
+    description: |
+      Any persona template (under app/modules/<m>/templates/<m>/{admin,merchant,store}/*.html)
+      that exceeds 75 LOC AND does not {% include %} a `*/shared/*` partial is likely
+      duplicating body content that should live in a shared partial used by all three
+      personas. See docs/architecture/persona-template-consolidation.md for the pattern.
+
+      RIGHT (thin wrapper + shared body):
+        {% extends "store/base.html" %}
+        ...page-header + loading/error...
+        {% set cards_api_prefix = '/store/loyalty' %}
+        {% set cards_base_url = '/store/' ~ store_code ~ '/loyalty/cards' %}
+        {% include 'loyalty/shared/cards-list.html' %}
+
+      WRONG (inlined table + filters that already exist in shared/):
+        {% extends "store/base.html" %}
+        ...200 lines of inline <table>/filters/pagination identical to merchant's...
+
+      Suppress for legit exceptions (admin multi-merchant aggregator, store-only
+      hardware UI, persona-unique tabbed dashboard) with `{# noqa: TPL-016 #}`
+      anywhere in the file.
+    pattern:
+      file_pattern: "app/modules/*/templates/*/{admin,merchant,store}/*.html"
+      threshold_loc: 75
+      required_pattern: "{% include .*/shared/.*"
+      exceptions:
+        - "base.html"
+        - "partials/"
+
   - id: "TPL-014"
     name: "Use new modal_simple macro API with call block"
     severity: "error"