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/tools_v2/__init__.py

@@ -26,7 +26,7 @@
 
 GNS3-Copilot Tools Package
 
-This package provides various tools for interacting with GNS3 network simulator, including:
+This package provides various tools for interacting with GNS3 network simulator:
 - Device configuration command execution
 - Display command execution
 - Multiple device command execution using Nornir
@@ -36,7 +36,7 @@ This package provides various tools for interacting with GNS3 network simulator,
 Main modules:
 - config_tools_nornir: Multiple device configuration command execution tool using Nornir
 - display_tools_nornir: Multiple device command execution tool using Nornir
-- vpcs_tools_telnetlib3: VPCS device configuration tool using telnetlib3 (concurrent execution)
+- vpcs_tools_telnetlib3: VPCS device configuration tool using telnetlib3
 - gns3_create_node: GNS3 node creation tool
 - gns3_create_link: GNS3 link creation tool
 - gns3_start_node: GNS3 node startup tool