[BUG] Extension node map scanner includes incorrect node names (false positives) for some custom nodes

The extension node map scanning logic used to generate `extension-node-map.json` appears to produce incorrect results for some custom nodes.

Using **ComfyUI-Lora-Manager** as an example, the current scan output includes multiple nodes that do **not** belong to this extension, which can lead to incorrect conflict detection in ComfyUI Manager.

### Actual Result

Current scan result for `https://github.com/willmiao/ComfyUI-Lora-Manager:`

```json
[
"BasicScheduler",
"CFGGuider",
"CLIPTextEncode",
"DebugMetadata",
"KSamplerSelect",
"LoraManagerLoader",
"LoraManagerTextLoader",
"LoraStacker",
"PromptLoraManager",
"SamplerCustomAdvanced",
"SaveImage",
"TSC_EfficientLoader",
"TriggerWordToggle",
"VAEDecode",
"WanVideoLoraSelect",
"WanVideoLoraSelectFromText"
]
```

### Expected Result

The scan result should only include nodes that are actually implemented and registered by this extension:

```json
[
"DebugMetadata",
"LoraManagerLoader",
"LoraManagerTextLoader",
"LoraStacker",
"PromptLoraManager",
"SaveImage",
"TriggerWordToggle",
"WanVideoLoraSelect",
"WanVideoLoraSelectFromText"
]
```

### Impact

Because of this incorrect mapping:

- ComfyUI Manager may report false-positive node conflicts

- Users may be warned about conflicts that do not actually exist