fix(providers): add Zhipu API error code 1210 to format error patterns

This fixes issue #2943 where WeChat channel image requests to Zhipu
GLM-5-Turbo vision API failed with error code 1210 (parameter error)
without triggering the fallback mechanism.

Changes:
- Added error code 1210 pattern matching to formatPatterns
- This allows the fallback mechanism to recognize Zhipu API parameter
  errors and fall back to alternative vision models

Closes #2943

pkg/providers/error_classifier.go

@@ -111,6 +111,10 @@ var (
 		substr("tool_use_id"),
 		substr("messages.1.content.1.tool_use.id"),
 		substr("invalid request format"),
+		// Zhipu API error code 1210: parameter error (e.g., image format incompatible)
+		substr("error code: 1210"),
+		substr("error code 1210"),
+		substr("zhipu api error code: 1210"),
 	}
 	contextOverflowPatterns = []errorPattern{
 		rxp(`context[_ ]?length[_ ]?exceeded`),