feat: update Gemini default model and remove Google Official preset model

Updated default model from gemini-2.5-pro to gemini-3-pro-preview across:
- Provider presets (PackyCode, Custom)
- Form field placeholders
- Default configurations
- Test cases

Google Official preset now has empty env config, allowing users to choose
their own model or use application defaults, which is more appropriate for
OAuth-based authentication.

Changes:
- geminiProviderPresets.ts: updated model to gemini-3-pro-preview, removed model from Google Official
- GeminiFormFields.tsx: updated placeholder to gemini-3-pro-preview
- GeminiConfigSections.tsx: updated placeholder to gemini-3-pro-preview
- ProviderForm.tsx: updated default config to gemini-3-pro-preview
- gemini_config.rs: updated test examples to gemini-3-pro-preview

src-tauri/src/gemini_config.rs

@@ -368,7 +368,7 @@ mod tests {
 # Comment line
 GOOGLE_GEMINI_BASE_URL=https://example.com
 GEMINI_API_KEY=sk-test123
-GEMINI_MODEL=gemini-2.5-pro
+GEMINI_MODEL=gemini-3-pro-preview
 
 # Another comment
 "#;
@@ -381,19 +381,19 @@ GEMINI_MODEL=gemini-2.5-pro
             Some(&"https://example.com".to_string())
         );
         assert_eq!(map.get("GEMINI_API_KEY"), Some(&"sk-test123".to_string()));
-        assert_eq!(map.get("GEMINI_MODEL"), Some(&"gemini-2.5-pro".to_string()));
+        assert_eq!(map.get("GEMINI_MODEL"), Some(&"gemini-3-pro-preview".to_string()));
     }
 
     #[test]
     fn test_serialize_env_file() {
         let mut map = HashMap::new();
         map.insert("GEMINI_API_KEY".to_string(), "sk-test".to_string());
-        map.insert("GEMINI_MODEL".to_string(), "gemini-2.5-pro".to_string());
+        map.insert("GEMINI_MODEL".to_string(), "gemini-3-pro-preview".to_string());
 
         let content = serialize_env_file(&map);
 
         assert!(content.contains("GEMINI_API_KEY=sk-test"));
-        assert!(content.contains("GEMINI_MODEL=gemini-2.5-pro"));
+        assert!(content.contains("GEMINI_MODEL=gemini-3-pro-preview"));
     }
 
     #[test]
@@ -417,7 +417,7 @@ GEMINI_MODEL=gemini-2.5-pro
 # Comment line
 GOOGLE_GEMINI_BASE_URL=https://example.com
 GEMINI_API_KEY=sk-test123
-GEMINI_MODEL=gemini-2.5-pro
+GEMINI_MODEL=gemini-3-pro-preview
 
 # Another comment
 "#;
@@ -432,7 +432,7 @@ GEMINI_MODEL=gemini-2.5-pro
             Some(&"https://example.com".to_string())
         );
         assert_eq!(map.get("GEMINI_API_KEY"), Some(&"sk-test123".to_string()));
-        assert_eq!(map.get("GEMINI_MODEL"), Some(&"gemini-2.5-pro".to_string()));
+        assert_eq!(map.get("GEMINI_MODEL"), Some(&"gemini-3-pro-preview".to_string()));
     }
 
     #[test]
@@ -598,7 +598,7 @@ KEY_WITH-DASH=value";
         let settings = serde_json::json!({
             "env": {
                 "GEMINI_API_KEY": "sk-test123",
-                "GEMINI_MODEL": "gemini-2.5-pro"
+                "GEMINI_MODEL": "gemini-3-pro-preview"
             }
         });
 
@@ -611,7 +611,7 @@ KEY_WITH-DASH=value";
         // 测试缺少 API Key 的非空配置在基本验证中可以通过（用户稍后填写）
         let settings = serde_json::json!({
             "env": {
-                "GEMINI_MODEL": "gemini-2.5-pro"
+                "GEMINI_MODEL": "gemini-3-pro-preview"
             }
         });
 

src/components/providers/forms/GeminiConfigSections.tsx

@@ -61,7 +61,7 @@ export const GeminiEnvSection: React.FC<GeminiEnvSectionProps> = ({
         onBlur={onBlur}
         placeholder={`GOOGLE_GEMINI_BASE_URL=https://your-api-endpoint.com/
 GEMINI_API_KEY=sk-your-api-key-here
-GEMINI_MODEL=gemini-2.5-pro`}
+GEMINI_MODEL=gemini-3-pro-preview`}
         rows={6}
         className="w-full px-3 py-2 border border-border-default dark:bg-gray-800 dark:text-gray-100 rounded-lg text-sm font-mono focus:outline-none focus:ring-2 focus:ring-blue-500/20 dark:focus:ring-blue-400/20 transition-colors resize-y min-h-[8rem]"
         autoComplete="off"

src/components/providers/forms/GeminiFormFields.tsx

@@ -127,7 +127,7 @@ export function GeminiFormFields({
             id="gemini-model"
             value={model}
             onChange={(e) => onModelChange(e.target.value)}
-            placeholder="gemini-2.5-pro"
+            placeholder="gemini-3-pro-preview"
           />
         </div>
       )}

src/components/providers/forms/ProviderForm.tsx

@@ -53,7 +53,7 @@ const GEMINI_DEFAULT_CONFIG = JSON.stringify(
     env: {
       GOOGLE_GEMINI_BASE_URL: "",
       GEMINI_API_KEY: "",
-      GEMINI_MODEL: "gemini-2.5-pro",
+      GEMINI_MODEL: "gemini-3-pro-preview",
     },
   },
   null,

src/config/geminiProviderPresets.ts

@@ -33,14 +33,11 @@ export const geminiProviderPresets: GeminiProviderPreset[] = [
     websiteUrl: "https://ai.google.dev/",
     apiKeyUrl: "https://aistudio.google.com/apikey",
     settingsConfig: {
-      env: {
-        GEMINI_MODEL: "gemini-2.5-pro",
-      },
+      env: {},
     },
     description: "Google 官方 Gemini API (OAuth)",
     category: "official",
     partnerPromotionKey: "google-official",
-    model: "gemini-2.5-pro",
     theme: {
       icon: "gemini",
       backgroundColor: "#4285F4",
@@ -54,11 +51,11 @@ export const geminiProviderPresets: GeminiProviderPreset[] = [
     settingsConfig: {
       env: {
         GOOGLE_GEMINI_BASE_URL: "https://www.packyapi.com",
-        GEMINI_MODEL: "gemini-2.5-pro",
+        GEMINI_MODEL: "gemini-3-pro-preview",
       },
     },
     baseURL: "https://www.packyapi.com",
-    model: "gemini-2.5-pro",
+    model: "gemini-3-pro-preview",
     description: "PackyCode",
     category: "third_party",
     isPartner: true,
@@ -74,10 +71,10 @@ export const geminiProviderPresets: GeminiProviderPreset[] = [
     settingsConfig: {
       env: {
         GOOGLE_GEMINI_BASE_URL: "",
-        GEMINI_MODEL: "gemini-2.5-pro",
+        GEMINI_MODEL: "gemini-3-pro-preview",
       },
     },
-    model: "gemini-2.5-pro",
+    model: "gemini-3-pro-preview",
     description: "自定义 Gemini API 端点",
     category: "custom",
   },