Add Codex OAuth provider flow for ChatGPT account sign-in (#503)

* feat: add Codex OAuth provider flow

* fix: harden Codex OAuth storage, session activation, and UI

src/services/api/providerConfig.runtimeCodexCredentials.test.ts

@@ -0,0 +1,107 @@
+import { afterEach, expect, mock, test } from 'bun:test'
+import { mkdtempSync, rmSync, writeFileSync } from 'node:fs'
+import { tmpdir } from 'node:os'
+import { join } from 'node:path'
+
+import { resolveRuntimeCodexCredentials } from './providerConfig.js'
+
+afterEach(() => {
+  mock.restore()
+})
+
+function makeJwt(payload: Record<string, unknown>): string {
+  const header = Buffer.from(JSON.stringify({ alg: 'none', typ: 'JWT' }))
+    .toString('base64url')
+  const body = Buffer.from(JSON.stringify(payload)).toString('base64url')
+  return `${header}.${body}.signature`
+}
+
+test('runtime credential resolution honors explicit auth.json over stored secure-storage tokens', () => {
+  const tempDir = mkdtempSync(join(tmpdir(), 'openclaude-codex-explicit-auth-'))
+  const authPath = join(tempDir, 'auth.json')
+
+  writeFileSync(
+    authPath,
+    JSON.stringify({
+      openai_api_key: makeJwt({
+        'https://api.openai.com/auth': {
+          chatgpt_account_id: 'acct_explicit_auth_json',
+        },
+      }),
+    }),
+    'utf8',
+  )
+
+  try {
+    const credentials = resolveRuntimeCodexCredentials({
+      env: {
+        CODEX_AUTH_JSON_PATH: authPath,
+      } as NodeJS.ProcessEnv,
+      storedCredentials: {
+        apiKey: 'stored-api-key',
+        accessToken: 'stored-access-token',
+        accountId: 'acct_stored',
+      },
+    })
+
+    expect(credentials.source).toBe('auth.json')
+    expect(credentials.accountId).toBe('acct_explicit_auth_json')
+    expect(credentials.apiKey).not.toBe('stored-api-key')
+  } finally {
+    rmSync(tempDir, { force: true, recursive: true })
+  }
+})
+
+test('runtime credential resolution preserves an explicit auth.json path even when it is missing', () => {
+  const tempDir = mkdtempSync(join(tmpdir(), 'openclaude-codex-missing-auth-'))
+  const authPath = join(tempDir, 'missing-auth.json')
+
+  try {
+    const credentials = resolveRuntimeCodexCredentials({
+      env: {
+        CODEX_AUTH_JSON_PATH: authPath,
+      } as NodeJS.ProcessEnv,
+      storedCredentials: {
+        apiKey: 'stored-api-key',
+        accessToken: 'stored-access-token',
+        accountId: 'acct_stored',
+      },
+    })
+
+    expect(credentials.source).toBe('none')
+    expect(credentials.authPath).toBe(authPath)
+    expect(credentials.apiKey).toBe('')
+  } finally {
+    rmSync(tempDir, { force: true, recursive: true })
+  }
+})
+
+test('runtime credential resolution avoids sync secure-storage reads when async credentials are provided', async () => {
+  let syncReadCalled = false
+
+  mock.module('../../utils/codexCredentials.js', () => ({
+    isCodexRefreshFailureCoolingDown: () => false,
+    readCodexCredentials: () => {
+      syncReadCalled = true
+      throw new Error('sync secure-storage read should not run in runtime resolution')
+    },
+  }))
+
+  // @ts-expect-error cache-busting query string for Bun module mocks
+  const { resolveRuntimeCodexCredentials } = await import(
+    './providerConfig.js?runtime-no-sync-secure-storage'
+  )
+
+  const credentials = resolveRuntimeCodexCredentials({
+    env: {} as NodeJS.ProcessEnv,
+    storedCredentials: {
+      accessToken: 'stored-access-token',
+      accountId: 'acct_stored',
+    },
+  })
+
+  expect(syncReadCalled).toBe(false)
+  expect(credentials.source).toBe('secure-storage')
+  expect(credentials.apiKey).toBe('stored-access-token')
+  expect(credentials.accountId).toBe('acct_stored')
+})