feat: add super admin bypass in tree list filter

Super admins now see all trees regardless of ownership, team, or
public/default status. Previously the build_tree_access_filter function
had no super_admin check, so admins could only see their own trees plus
public/default/team trees.

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

backend/app/api/endpoints/trees.py

@@ -2,7 +2,7 @@ from typing import Annotated, Optional
 from uuid import UUID
 from fastapi import APIRouter, Depends, HTTPException, status, Query
 from sqlalchemy.ext.asyncio import AsyncSession
-from sqlalchemy import select, func, or_
+from sqlalchemy import select, func, or_, true as sa_true
 from sqlalchemy.orm import selectinload
 
 from app.core.database import get_db
@@ -22,17 +22,22 @@ def build_tree_access_filter(current_user: User):
     """Build the access filter for trees based on user permissions.
 
     Returns trees that are:
+    - All trees (for super admins)
     - Default/system trees (visible to all)
     - Public trees
     - User's own trees
     - Trees from user's team
     """
-    return or_(
+    if current_user.is_super_admin:
+        return sa_true()
+    conditions = [
         Tree.is_default == True,
         Tree.is_public == True,
         Tree.author_id == current_user.id,
-        Tree.team_id == current_user.team_id if current_user.team_id else False
-    )
+    ]
+    if current_user.team_id:
+        conditions.append(Tree.team_id == current_user.team_id)
+    return or_(*conditions)
 
 
 def build_tree_response(tree: Tree) -> TreeListResponse: