fix(proxy): separate upstream target resolution from proxy dispatch and add site-level proxy URLs

src/server/routes/proxy/endpointFlow.test.ts

@@ -73,6 +73,7 @@ describe('executeEndpointFlow', () => {
 
     expect(result.ok).toBe(true);
     expect(dispatchRequest).toHaveBeenCalledTimes(1);
+    expect(dispatchRequest.mock.calls[0]?.[1]).toBe('https://example.com/v1/responses');
     expect(fetchMock).not.toHaveBeenCalled();
   });
 
@@ -219,22 +220,6 @@ describe('executeEndpointFlow', () => {
     expect(fetchMock).toHaveBeenCalledTimes(1);
   });
 
-  it('uses proxyUrl for the default fetch path when no dispatch hook is provided', async () => {
-    fetchMock.mockResolvedValueOnce(toUndiciResponse(new Response(JSON.stringify({ ok: true }), {
-      status: 200,
-      headers: { 'content-type': 'application/json' },
-    })));
-
-    await executeEndpointFlow({
-      siteUrl: 'https://example.com',
-      proxyUrl: 'https://proxy.internal/base',
-      endpointCandidates: ['responses'],
-      buildRequest: () => requestFor('/v1/responses'),
-    });
-
-    expect(fetchMock.mock.calls[0]?.[0]).toBe('https://proxy.internal/base/v1/responses');
-  });
-
   it('returns normalized final error when all endpoints fail', async () => {
     fetchMock.mockResolvedValueOnce(toUndiciResponse(new Response(JSON.stringify({
       error: { message: 'upstream_error', type: 'upstream_error' },

src/server/routes/proxy/endpointFlow.ts

@@ -59,7 +59,6 @@ export function withUpstreamPath(path: string, message: string): string {
 
 type ExecuteEndpointFlowInput = {
   siteUrl: string;
-  proxyUrl?: string | null;
   endpointCandidates: UpstreamEndpoint[];
   buildRequest: (endpoint: UpstreamEndpoint, endpointIndex: number) => BuiltEndpointRequest;
   dispatchRequest?: (
@@ -73,12 +72,6 @@ type ExecuteEndpointFlowInput = {
   onAttemptSuccess?: (ctx: EndpointAttemptSuccessContext) => void | Promise<void>;
 };
 
-function buildAbsoluteUrl(base: string, path: string): string {
-  const normalizedBase = base.replace(/\/+$/, '');
-  const normalizedPath = path.replace(/^\/+/, '');
-  return normalizedPath ? `${normalizedBase}/${normalizedPath}` : normalizedBase;
-}
-
 export async function executeEndpointFlow(input: ExecuteEndpointFlowInput): Promise<EndpointFlowResult> {
   const endpointCount = input.endpointCandidates.length;
   if (endpointCount <= 0) {
@@ -96,10 +89,7 @@ export async function executeEndpointFlow(input: ExecuteEndpointFlowInput): Prom
   for (let endpointIndex = 0; endpointIndex < endpointCount; endpointIndex += 1) {
     const endpoint = input.endpointCandidates[endpointIndex] as UpstreamEndpoint;
     const request = input.buildRequest(endpoint, endpointIndex);
-    const defaultTarget = buildUpstreamUrl(input.siteUrl, request.path);
-    const targetUrl = input.proxyUrl
-      ? buildAbsoluteUrl(input.proxyUrl, request.path)
-      : defaultTarget;
+    const targetUrl = buildUpstreamUrl(input.siteUrl, request.path);
 
     let response = input.dispatchRequest
       ? await input.dispatchRequest(request, targetUrl)