fix: update Paperless webhook payload to match include_document format

- Change model field from document_id to id (Paperless sends id)
- Add content, created, modified, added, original_file_name, owner fields
- Add extra="ignore" config to handle additional Paperless fields
- Update sync service to use content from webhook payload
- Skip Paperless API call when content already provided

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/models/document.py

@@ -86,13 +86,22 @@ class DocumentUploadResponse(BaseModel):
 
 
 class PaperlessWebhookPayload(BaseModel):
-    """Payload from Paperless-ngx webhook."""
-    document_id: int = Field(..., description="Paperless document ID")
-    event: str = Field(..., description="Event type (document_added, document_updated)")
+    """Payload from Paperless-ngx webhook (include_document=true format)."""
+    id: int = Field(..., description="Paperless document ID")
     title: Optional[str] = Field(None, description="Document title")
+    content: Optional[str] = Field(None, description="Document text content")
     correspondent: Optional[int] = Field(None, description="Correspondent ID")
     document_type: Optional[int] = Field(None, description="Document type ID")
     tags: List[int] = Field(default_factory=list, description="Tag IDs")
+    created: Optional[str] = Field(None, description="Created date")
+    modified: Optional[str] = Field(None, description="Modified datetime")
+    added: Optional[str] = Field(None, description="Added datetime")
+    original_file_name: Optional[str] = Field(None, description="Original filename")
+    owner: Optional[int] = Field(None, description="Owner user ID")
+    custom_fields: List[Dict[str, Any]] = Field(default_factory=list, description="Custom fields")
+
+    class Config:
+        extra = "ignore"  # Ignore extra fields from Paperless
 
 
 class WebhookResponse(BaseModel):