fix(bailian): add missing workspaceId tests, fix supportsPromptCache fallback (#420)(#421)

- src/api/providers/__tests__/bailian.spec.ts — add negative tests for
  Frankfurt and Hong Kong region construction without workspaceId
- webview-ui/src/components/settings/providers/Bailian.tsx — align
  supportsPromptCache checkbox fallback with supportsImages pattern
  (fall back to defaultInfo.supportsPromptCache)

Author: F915

src/api/providers/__tests__/bailian.spec.ts

@@ -248,3 +248,16 @@ describe("BailianHandler", () => {
 	})
 
 })
+		it("should throw when Frankfurt region is used without workspaceId", () => {
+			expect(
+				() => new BailianHandler({ bailianApiKey: "test-key", bailianRegion: "frankfurt" }),
+			).toThrow()
+		})
+
+		it("should throw when Hong Kong region is used without workspaceId", () => {
+			expect(
+				() => new BailianHandler({ bailianApiKey: "test-key", bailianRegion: "hongkong" }),
+			).toThrow()
+		})
+
+

webview-ui/src/components/settings/providers/Bailian.tsx

@@ -233,7 +233,7 @@ export const Bailian = ({
 					<div>
 						<div className="flex items-center gap-1">
 							<Checkbox
-								checked={customInfo?.supportsPromptCache ?? false}
+								checked={customInfo?.supportsPromptCache ?? defaultInfo.supportsPromptCache ?? false}
 								onChange={handleInputChange("bailianCustomModelInfo", (checked) => {
 									return {
 										...(customInfo || makeBase()),