feat: add MiMo reasoning_content support for Claude Code proxy (#2990)

* feat: add MiMo reasoning_content support for Claude Code proxy

MiMo requires reasoning_content to be passed back in multi-turn
conversations with tool calls. Add "mimo" and "xiaomimimo" to the
preserve_reasoning_content whitelist so thinking blocks are converted
to reasoning_content when proxying Claude Code → MiMo.

Also handle redacted_thinking blocks (encrypted by Claude Code across
turns) by injecting a placeholder to prevent MiMo 400 errors.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

* fix: support MiMo reasoning histories

- Fix the PR CI clippy failure for redacted thinking handling.
- Preserve MiMo reasoning content on the OpenAI Chat proxy path.
- Normalize Claude Desktop Anthropic thinking history for MiMo local routes.
- Reject unsupported Claude Desktop direct model remaps.

---------

Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
Co-authored-by: Jason <farion1231@gmail.com>

src-tauri/src/proxy/providers/claude.rs

@@ -84,7 +84,11 @@ pub fn claude_api_format_needs_transform(api_format: &str) -> bool {
 
 fn is_reasoning_content_compatible_identifier(value: &str) -> bool {
     let value = value.to_ascii_lowercase();
-    value.contains("moonshot") || value.contains("kimi") || value.contains("deepseek")
+    value.contains("moonshot")
+        || value.contains("kimi")
+        || value.contains("deepseek")
+        || value.contains("mimo")
+        || value.contains("xiaomimimo")
 }
 
 fn should_preserve_reasoning_content_for_openai_chat(
@@ -1801,4 +1805,39 @@ mod tests {
         assert_eq!(msg["reasoning_content"], "I should call the tool.");
         assert!(msg.get("tool_calls").is_some());
     }
+
+    #[test]
+    fn test_transform_openai_chat_preserves_reasoning_content_for_mimo_provider() {
+        let provider = create_provider_with_meta(
+            json!({
+                "env": {
+                    "ANTHROPIC_BASE_URL": "https://api.xiaomimimo.com/v1",
+                    "ANTHROPIC_API_KEY": "test-key"
+                }
+            }),
+            ProviderMeta {
+                api_format: Some("openai_chat".to_string()),
+                ..Default::default()
+            },
+        );
+        let body = json!({
+            "model": "mimo-v2.5-pro",
+            "max_tokens": 64,
+            "messages": [{
+                "role": "assistant",
+                "content": [
+                    {"type": "thinking", "thinking": "I should call the tool."},
+                    {"type": "tool_use", "id": "call_123", "name": "get_weather", "input": {"location": "Tokyo"}}
+                ]
+            }]
+        });
+
+        let transformed =
+            transform_claude_request_for_api_format(body, &provider, "openai_chat", None, None)
+                .unwrap();
+
+        let msg = &transformed["messages"][0];
+        assert_eq!(msg["reasoning_content"], "I should call the tool.");
+        assert!(msg.get("tool_calls").is_some());
+    }
 }

src-tauri/src/proxy/providers/transform.rs

@@ -438,6 +438,14 @@ fn convert_message_to_openai(
                         }
                     }
                 }
+                "redacted_thinking" if preserve_reasoning_content => {
+                    // Claude Code encrypts historical thinking into redacted_thinking blocks.
+                    // MiMo/DeepSeek require non-empty reasoning_content on assistant tool-call
+                    // messages, so inject a minimal placeholder when the real content is
+                    // unavailable. Skip when preserve_reasoning_content is off (generic
+                    // OpenAI-compatible path).
+                    reasoning_parts.push("[redacted thinking]".to_string());
+                }
                 _ => {}
             }
         }
@@ -950,6 +958,26 @@ mod tests {
         assert_eq!(msg["tool_calls"][0]["id"], "call_123");
     }
 
+    #[test]
+    fn test_anthropic_to_openai_tool_use_uses_redacted_thinking_placeholder() {
+        let input = json!({
+            "model": "mimo-v2.5-pro",
+            "max_tokens": 1024,
+            "messages": [{
+                "role": "assistant",
+                "content": [
+                    {"type": "redacted_thinking", "data": "opaque"},
+                    {"type": "tool_use", "id": "call_123", "name": "get_weather", "input": {"location": "Tokyo"}}
+                ]
+            }]
+        });
+
+        let result = anthropic_to_openai_with_reasoning_content(input, true).unwrap();
+        let msg = &result["messages"][0];
+        assert_eq!(msg["reasoning_content"], "[redacted thinking]");
+        assert_eq!(msg["tool_calls"][0]["id"], "call_123");
+    }
+
     #[test]
     fn test_anthropic_to_openai_does_not_emit_reasoning_content_by_default() {
         let input = json!({