feat: consolidate env config and add deployment files

- Add debug_font_path, demo_docs_dir, e2e_api_base_url to config.py
- Fix hardcoded paths in pp_structure_debug.py, create_demo_images.py
- Fix hardcoded paths in test files
- Update .env.example with new configuration options
- Update .gitignore to exclude AI development files (.claude/, openspec/, AGENTS.md, CLAUDE.md)
- Add production startup script (start-prod.sh)
- Add README.md with project documentation
- Add 1panel Docker deployment files (docker-compose.yml, Dockerfiles, nginx.conf)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

backend/app/services/memory_manager.py

@@ -1336,31 +1336,31 @@ class PriorityOperationQueue:
             # Wait for an item
             if not self._queue:
                 if timeout is not None:
-                    result = self._condition.wait_for(
-                        lambda: len(self._queue) > 0,
-                        timeout=timeout
-                    )
+                    result = self._condition.wait_for(lambda: len(self._queue) > 0, timeout=timeout)
                     if not result:
                         return None
                 else:
                     return None
 
-            # Get highest priority item
-            neg_priority, _, item_id, data = heapq.heappop(self._queue)
-            priority = BatchPriority(-neg_priority)
+            # Keep popping until we find a non-cancelled item (or queue is exhausted)
+            while self._queue:
+                neg_priority, _, item_id, data = heapq.heappop(self._queue)
+                priority = BatchPriority(-neg_priority)
 
-            # Skip if cancelled
-            if item_id in self._cancelled:
-                self._cancelled.discard(item_id)
-                self._total_cancelled += 1
+                if item_id in self._cancelled:
+                    self._cancelled.discard(item_id)
+                    self._total_cancelled += 1
+                    self._condition.notify()
+                    continue
+
+                self._total_dequeued += 1
                 self._condition.notify()
-                return self.dequeue(timeout=0)  # Try next item
+                logger.debug(f"Dequeued operation {item_id} with priority {priority.name}")
+                return item_id, data, priority
 
-            self._total_dequeued += 1
-            self._condition.notify()
+            return None
 
-        logger.debug(f"Dequeued operation {item_id} with priority {priority.name}")
-        return item_id, data, priority
+        return None
 
     def cancel(self, item_id: str) -> bool:
         """