Add Skins format, GolfCourseAPI import, and UX improvements

- Add Skins game format with optional carryover, mirroring BBB scoring pattern
- Add GolfCourseAPI integration for course search and import (httpx)
- Unwrap {"course": {}} API response envelope on import
- Add searchable course combobox and player filter to new game form
- Redirect to summary page after finishing a game
- Fix auth to allow registered users without a pending invitation
- Fix hardcoded BBB format in create_game; store carryover flag in DB
- Add game summary/scorecard view for completed games
- Add live games social stream to dashboard
- Add course name + subtitle to recent game cards
- Reorder nav: Home → Games → Admin → Profile

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

app/templates/admin/courses.html

@@ -17,7 +17,8 @@
   <div class="alert alert-success">{{ request.query_params.get('success') }}</div>
   {% endif %}
 
-  <div style="display:flex; justify-content:flex-end; margin-bottom:1rem;">
+  <div style="display:flex; gap:0.5rem; justify-content:flex-end; margin-bottom:1rem;">
+    <a href="/admin/courses/search" class="btn" style="width:auto; padding:0.5rem 1rem; background:var(--surface2); color:var(--text);">Search & Import</a>
     <a href="/admin/courses/new" class="btn btn-primary" style="width:auto; padding:0.5rem 1rem;">+ New course</a>
   </div>