feat(copilot): add copilot_mode field and config command tool

- Add `copilot_mode` field to LLM model configs API with "teaching" (diagnostics only) and "lab_assistant" (full configuration access) modes
- Introduce new `ExecuteMultipleDeviceConfigCommands` tool for executing configuration commands on multiple devices
- Include `tags` field in node data structure for enhanced project management
- Update API documentation examples to reflect new `copilot_mode` field and context limit additions

gns3server/schemas/controller/llm_model_configs.py

@@ -48,9 +48,14 @@ class LLMModelConfigData(BaseModel):
     context_strategy: Literal["conservative", "balanced", "aggressive"] = Field(
         "balanced", description="Context trimming strategy: conservative (60%), balanced (75%), aggressive (85%)"
     )
+    copilot_mode: Optional[str] = Field(
+        None,
+        description="GNS3-Copilot mode: 'teaching' (diagnostics only) or 'lab_assistant' (full configuration access)"
+    )
 
     # Allow extra fields for extensibility
-    model_config = ConfigDict(extra="allow")
+    # Ensure all fields are included in serialization, even if None
+    model_config = ConfigDict(extra="allow", populate_by_name=True)
 
 
 # Request schemas
@@ -71,6 +76,10 @@ class LLMModelConfigCreate(BaseModel):
     context_strategy: Literal["conservative", "balanced", "aggressive"] = Field(
         "balanced", description="Context trimming strategy"
     )
+    copilot_mode: Optional[str] = Field(
+        None,
+        description="GNS3-Copilot mode: 'teaching' (diagnostics only) or 'lab_assistant' (full configuration access)"
+    )
 
     # Allow extra config fields
     model_config = ConfigDict(extra="allow")
@@ -96,6 +105,10 @@ class LLMModelConfigUpdate(BaseModel):
     context_strategy: Optional[Literal["conservative", "balanced", "aggressive"]] = Field(
         None, description="Context trimming strategy"
     )
+    copilot_mode: Optional[str] = Field(
+        None,
+        description="GNS3-Copilot mode: 'teaching' (diagnostics only) or 'lab_assistant' (full configuration access)"
+    )
 
     # Allow extra config fields
     model_config = ConfigDict(extra="allow")