fix: identify OpenCode Go requests by session

packages/web/server/lib/quota/providers/opencode-go.js

@@ -37,6 +37,7 @@ export const fetchOpenCodeGoUsage = async (apiKey, fetchImpl = fetch) => {
     headers: {
       Accept: 'application/json',
       Authorization: `Bearer ${apiKey}`,
+      'x-opencode-session': 'openchamber-usage',
       'User-Agent': 'OpenChamber quota provider',
     },
     signal: AbortSignal.timeout(15_000),

packages/web/server/lib/quota/providers/opencode-go.test.js

@@ -43,7 +43,11 @@ describe('OpenCode Go quota provider', () => {
       return new Response(JSON.stringify({ usage: { rolling: { percent: 25, resetsAt: '2026-08-12T12:00:00.000Z' } } }));
     });
     expect(request.url).toBe('https://opencode.ai/zen/go/v1/usage');
-    expect(request.options.headers).toMatchObject({ Accept: 'application/json', Authorization: 'Bearer secret' });
+    expect(request.options.headers).toMatchObject({
+      Accept: 'application/json',
+      Authorization: 'Bearer secret',
+      'x-opencode-session': 'openchamber-usage',
+    });
     expect(request.options.headers.Cookie).toBeUndefined();
     expect(usage['5h'].usedPercent).toBe(25);
   });