Convert last Python fragment handlers to SX defhandlers: 100% declarative fragment API

- Add dict recursion to _convert_result for service methods returning dict[K, list[DTO]]
- New container-cards.sx: parses post_ids/slugs, calls confirmed-entries-for-posts, emits card-widget markers
- New account-page.sx: dispatches on slug for tickets/bookings panels with status pills and empty states
- Fix blog _parse_card_fragments to handle SxExpr via str() cast
- Remove events Python fragment handlers and simplify app.py to plain auto_mount

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

shared/sx/primitives_io.py

@@ -242,6 +242,8 @@ def _convert_result(result: Any) -> Any:
     if result is None:
         from .types import NIL
         return NIL
+    if isinstance(result, dict):
+        return {k: _convert_result(v) for k, v in result.items()}
     if isinstance(result, tuple):
         # Tuple returns (e.g. (entries, has_more)) → list for sx access
         return [_convert_result(item) for item in result]