Convert social and federation profile from Jinja to SX rendering

Add primitives (replace, strip-tags, slice, csrf-token), convert all
social blueprint routes and federation profile to SX content builders,
delete 12 unused Jinja templates and social_lite layout.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

shared/infrastructure/factory.py

@@ -160,6 +160,8 @@ def create_base_app(
     # Auto-register per-app social blueprint (not federation — it has its own)
     if name in AP_APPS and name != "federation":
         from shared.infrastructure.ap_social import create_ap_social_blueprint
+        from shared.infrastructure.ap_social_sx import setup_social_layout
+        setup_social_layout()
         app.register_blueprint(create_ap_social_blueprint(name))
 
     # --- device id (all apps, including account) ---