Remove unsupported Gemini 2.5 Flash Image Preview free model

- Remove 'google/gemini-2.5-flash-image-preview:free' from IMAGE_GENERATION_MODELS array in generateImageTool.ts
- Remove free model option from UI ImageGenerationSettings component
- Update test files to use paid version instead of free version
- All tests passing after changes

The free endpoint is no longer supported, only the paid version remains available.

Author: SannidhyaSah

src/core/tools/generateImageTool.ts

@@ -11,7 +11,7 @@ import { EXPERIMENT_IDS, experiments } from "../../shared/experiments"
 import { OpenRouterHandler } from "../../api/providers/openrouter"
 
 // Hardcoded list of image generation models for now
-const IMAGE_GENERATION_MODELS = ["google/gemini-2.5-flash-image-preview", "google/gemini-2.5-flash-image-preview:free"]
+const IMAGE_GENERATION_MODELS = ["google/gemini-2.5-flash-image-preview"]
 
 export async function generateImageTool(
 	cline: Task,

webview-ui/src/components/settings/ImageGenerationSettings.tsx

@@ -14,7 +14,6 @@ interface ImageGenerationSettingsProps {
 // Hardcoded list of image generation models
 const IMAGE_GENERATION_MODELS = [
 	{ value: "google/gemini-2.5-flash-image-preview", label: "Gemini 2.5 Flash Image Preview" },
-	{ value: "google/gemini-2.5-flash-image-preview:free", label: "Gemini 2.5 Flash Image Preview (Free)" },
 	// Add more models as they become available
 ]
 

webview-ui/src/components/settings/__tests__/ImageGenerationSettings.spec.tsx

@@ -41,7 +41,7 @@ describe("ImageGenerationSettings", () => {
 				<ImageGenerationSettings
 					{...defaultProps}
 					openRouterImageApiKey="existing-key"
-					openRouterImageGenerationSelectedModel="google/gemini-2.5-flash-image-preview:free"
+					openRouterImageGenerationSelectedModel="google/gemini-2.5-flash-image-preview"
 				/>,
 			)