Update NameWithIcon

The `NameWithIcon()` function had a `platform` parameter that was immediately overwritten by `platform = None` and never used (dead code). The function mixed data lookup (database queries via IDs) with rendering, making it untestable.

**Fix**: Refactored `NameWithIcon()` to follow the `LinkedPurchase` pattern — accepts model objects (`Game`, `Session`) instead of IDs. Extracted `_resolve_name_with_icon()` helper for testable computation logic (name resolution, platform extraction, link creation). Fixed bug where `platform` was not extracted when `session` parameter was passed. Removed dead `platform` parameter from the public API. Updated all 3 production call sites (already using model objects). Added 10 unit tests for `_resolve_name_with_icon()` covering session override, custom names, linkify behavior, platform resolution, and edge cases. Updated 6 integration tests to use model-based parameters.

games/views/session.py

@@ -131,7 +131,7 @@ def list_sessions(request: HttpRequest, search_string: str = "") -> HttpResponse
                     "hx_select": f"#session-row-{session.pk}",
                     "hx_swap": "outerHTML",
                     "cell_data": [
-                        NameWithIcon(session_id=session.pk),
+                        NameWithIcon(session=session),
                         f"{local_strftime(session.timestamp_start)}{f' — {local_strftime(session.timestamp_end, timeformat)}' if session.timestamp_end else ''}",
                         session.duration_formatted_with_mark,
                         render_to_string(