fix(marker): fix inheritance hook, topology load, update sync, and asdict

Bugs found via end-to-end testing of project-level marker definitions:

1. New links didn't inherit — apply_defs_to_new_link is async but was
   called without await in UDPLink.create().

2. Project load crashed — load_project passed marker_definitions to
   Project.__init__. Now popped in load_project and restored separately
   in Project.open() (it backs a read-only property).

3. PUT on a definition didn't sync to links — update_marker's guard
   rejected even the project-layer sync call. Added an `inherited`
   bypass flag used by update_marker_definition.

4. _ubridge_add_marker_filter raised re.PatternError — the name regex
   used (?i)(?!global) look-around, invalid in Python's re module.
   Dropped the prefix check there: "global-*" names are legitimate at
   the uBridge boundary (inherited definitions); forbidden only at the
   user-facing schema.

5. GET /links hid inherited markers — asdict()'s runtime branch used
   _persist_markers() (which filters inherited markers). Restored
   self._markers for the runtime branch; only the topology_dump branch
   filters (inherited markers are rebuilt from definitions on load).

6. Duplicate "already exists" warnings on project open — open() fanned
   out definitions to all links, but UDPLink.create() had already done
   so via its inheritance hook. Removed the redundant fan-out in open().

gns3server/controller/udp_link.py

@@ -147,7 +147,7 @@ class UDPLink(Link):
         self._created = True
         # New links automatically inherit every active project-level marker
         # definition so the user doesn't have to reconfigure.
-        self._project.apply_defs_to_new_link(self)
+        await self._project.apply_defs_to_new_link(self)
 
     async def update(self):
         """
@@ -391,7 +391,7 @@ class UDPLink(Link):
         self._project.emit_notification("link.updated", self.asdict())
         self._project.dump()
 
-    async def update_marker(self, name, bpf=None, tag=None, enabled=None, color=None):
+    async def update_marker(self, name, bpf=None, tag=None, enabled=None, color=None, inherited=False):
         """
         Update an existing marker's BPF/tag/enabled/color. Any change pushes via
         ``self.update()``; uBridge picks up the new params on the next NIO
@@ -402,13 +402,15 @@ class UDPLink(Link):
         :param tag: new tag id (None = keep existing)
         :param enabled: toggle (None = keep existing)
         :param color: new hex color (None = keep existing)
+        :param inherited: set by project-level sync to bypass the inheritance
+            guard (the project layer is the legitimate editor)
         """
 
         marker_info = self._markers.get(name)
         if not marker_info:
             raise ControllerNotFoundError(f"Marker '{name}' not found on link {self._id}")
 
-        if marker_info.get("inherited_from"):
+        if marker_info.get("inherited_from") and not inherited:
             raise ControllerError(
                 f"Marker '{name}' is inherited from the project-level "
                 f"definition '{marker_info['inherited_from']}'. "