style: fix E501 line-too-long errors in gns3_copilot

Fix all 423 E501 line length violations across 26 files to comply with
   PEP 8 88-character line limit.

   Changes:
   - Split long f-strings across multiple lines
   - Break long docstring descriptions and parameter lists
   - Split markdown table rows and list examples
   - Break long URL construction f-strings
   - Split long logger messages and comments
   - Add noqa: E501 for SVG strings (cannot be split)

   Modified files:
   - agent/: context_manager.py, gns3_copilot.py, model_factory.py
   - gns3_client/: connector_factory.py, context_helpers.py, custom_gns3fy.py,
                   gns3_project_info.py, gns3_topology_reader.py
   - prompts/: __init__.py, lab_automation_assistant_prompt.py,
               prompt_loader.py, teaching_assistant_prompt.py
   - tools_v2/: __init__.py, config_tools_nornir.py, display_tools_nornir.py,
                gns3_create_link.py, gns3_create_node.py, gns3_get_node_temp.py,
                gns3_start_node.py, gns3_update_node_name.py,
                vpcs_tools_telnetlib3.py
   - utils/: __init__.py, command_filter.py, get_gns3_device_port.py,
             gns3_drawing_utils.py, llm_config_helper.py, message_converters.py,
             parse_tool_content.py, tool_call_stream.py

   All files now pass ruff E501 checks.

   Co-Authored-By: Yue Guobin <yueguobin@outlook.com>

gns3server/agent/gns3_copilot/project_agent_manager.py

@@ -27,7 +27,8 @@
 Project Agent Manager
 
 Manages AgentService instances for GNS3 projects using a singleton pattern.
-Each project has its own AgentService with a dedicated SQLite checkpoint database.
+Each project has its own AgentService with a dedicated SQLite checkpoint
+database.
 """
 
 import asyncio
@@ -60,7 +61,9 @@ class ProjectAgentManager:
             cls._instance._lock = asyncio.Lock()
         return cls._instance
 
-    async def get_agent(self, project_id: str, project_path: str) -> AgentService:
+    async def get_agent(
+        self, project_id: str, project_path: str
+    ) -> AgentService:
         """
         Get or create an AgentService for a project.
 
@@ -73,7 +76,11 @@ class ProjectAgentManager:
         """
         async with self._lock:
             if project_id not in self._agents:
-                log.info("Creating new AgentService for project: %s at %s", project_id, project_path)
+                log.info(
+                    "Creating new AgentService for project: %s at %s",
+                    project_id,
+                    project_path,
+                )
                 self._agents[project_id] = AgentService(project_path)
             return self._agents[project_id]
 
@@ -99,7 +106,10 @@ class ProjectAgentManager:
         Should be called on server shutdown.
         """
         async with self._lock:
-            log.info("Closing all AgentService instances (%d projects)", len(self._agents))
+            log.info(
+                "Closing all AgentService instances (%d projects)",
+                len(self._agents),
+            )
             for project_id, agent in self._agents.items():
                 log.debug("Closing AgentService for project: %s", project_id)
                 await agent.close()