feat: add search_by_appearance agent tool for clothing color search

- New Python script: clothing_color_search.py
- New agent tool: search_by_appearance (red, blue, green, etc.)
- Uses appearance.json person bboxes + HSV color analysis
- Returns matched frames with confidence scores

src/api/agent_search.rs

@@ -276,6 +276,15 @@ fn make_tools(pool: &sqlx::PgPool) -> Vec<ToolDef> {
             }),
             vec!["file_uuid", "node_id"],
         ),
+        function_calling::make_tool(
+            "search_by_appearance",
+            "根據衣服顏色搜尋影片中的人物。支援顏色：red, orange, yellow, green, cyan, blue, purple, white, black。",
+            serde_json::json!({
+                "file_uuid": {"type": "string", "description": "影片 UUID"},
+                "color": {"type": "string", "description": "目標顏色: red, orange, yellow, green, cyan, blue, purple, white, black"}
+            }),
+            vec!["file_uuid", "color"],
+        ),
     ]
 }
 
@@ -310,6 +319,7 @@ async fn execute_tool(pool: &sqlx::PgPool, tool_call: &ToolCall) -> (String, Str
         "get_file_info" => tools::exec_get_file_info(pool, &args).await,
         "get_representative_frame" => tools::exec_get_representative_frame(pool, &args).await,
         "analyze_frame" => tools::exec_analyze_frame(pool, &args).await,
+        "search_by_appearance" => tools::exec_search_by_appearance(pool, &args).await,
         _ => Err(format!("Unknown tool: {}", name)),
     };
     let content = match result {

src/core/agent/tools.rs

@@ -1092,3 +1092,68 @@ pub async fn exec_tkg_node_detail(
         None => Err("Node not found".to_string()),
     }
 }
+
+/// Search for people by clothing color using appearance data
+pub async fn exec_search_by_appearance(pool: &sqlx::PgPool, args: &serde_json::Value) -> Result<String, String> {
+    let file_uuid = args.get("file_uuid")
+        .and_then(|v| v.as_str())
+        .ok_or("file_uuid is required".to_string())?;
+    let color = args.get("color")
+        .and_then(|v| v.as_str())
+        .ok_or("color is required (red, blue, green, yellow, orange, cyan, purple, white, black)".to_string())?;
+
+    let output_dir = std::env::var("MOMENTRY_OUTPUT_DIR")
+        .unwrap_or_else(|_| "/Users/accusys/momentry/output".to_string());
+    let scripts_dir = std::env::var("MOMENTRY_SCRIPTS_DIR")
+        .unwrap_or_else(|_| "/Users/accusys/momentry_core/scripts".to_string());
+    let script_path = format!("{}/clothing_color_search.py", scripts_dir);
+    let appearance_path = format!("{}/{}.appearance.json", output_dir, file_uuid);
+    let output_path = format!("{}/{}.color_search_{}.json", output_dir, file_uuid, color);
+
+    if !std::path::Path::new(&appearance_path).exists() {
+        return Err(format!("appearance.json not found for file {}", file_uuid));
+    }
+
+    // Get video path from videos table
+    let videos_table = schema::table_name("videos");
+    let video_path: Option<String> = sqlx::query_scalar(&format!(
+        "SELECT file_path FROM {} WHERE file_uuid = $1", videos_table
+    ))
+    .bind(file_uuid)
+    .fetch_optional(pool)
+    .await
+    .map_err(|e| e.to_string())?;
+
+    let video_path = video_path.unwrap_or_default();
+    if video_path.is_empty() {
+        return Err("Video path not found".to_string());
+    }
+
+    let executor = crate::core::processor::PythonExecutor::new()
+        .map_err(|e| e.to_string())?;
+    
+    executor.run(
+        &script_path,
+        &[
+            "--file-uuid", file_uuid,
+            "--color", color,
+            "--video-path", &video_path,
+            "--appearance-path", &appearance_path,
+            "--output", &output_path,
+        ],
+        None,
+        "CLOTHING_COLOR_SEARCH",
+        Some(std::time::Duration::from_secs(300)),
+    )
+    .await
+    .map_err(|e| e.to_string())?;
+
+    // Read results
+    if std::path::Path::new(&output_path).exists() {
+        let content = std::fs::read_to_string(&output_path)
+            .map_err(|e| e.to_string())?;
+        Ok(content)
+    } else {
+        Err("Color search output not found".to_string())
+    }
+}