Route third-party first-run setup into the provider wizard (#261)

The login picker previously sent third-party users to a dead-end info screen
that only mentioned env vars. This change reuses the existing provider wizard
from the login flow so first-run setup can continue without requiring slash
command access first.

Constraint: The existing provider setup logic must remain the single source of truth
Rejected: Build a separate third-party auth wizard in ConsoleOAuthFlow | would duplicate provider setup behavior and drift over time
Confidence: high
Scope-risk: moderate
Reversibility: clean
Directive: Keep third-party onboarding routed through ProviderWizard unless the provider command flow is intentionally redesigned
Tested: bun test src/components/ConsoleOAuthFlow.test.tsx src/commands/provider/provider.test.tsx
Tested: tsc --noEmit via project diagnostics
Not-tested: Live gh-authenticated push and PR creation path

Co-authored-by: anandh8x <test@example.com>

src/commands/provider/provider.tsx

@@ -903,7 +903,11 @@ function resolveCodexCredentials(processEnv: NodeJS.ProcessEnv):
   }
 }
 
-function ProviderWizard({ onDone }: { onDone: LocalJSXCommandOnDone }): React.ReactNode {
+export function ProviderWizard({
+  onDone,
+}: {
+  onDone: LocalJSXCommandOnDone
+}): React.ReactNode {
   const defaults = getProviderWizardDefaults()
   const [step, setStep] = React.useState<Step>({ name: 'choose' })
 

src/components/ConsoleOAuthFlow.test.tsx

@@ -0,0 +1,117 @@
+import { PassThrough } from 'node:stream'
+
+import { expect, test } from 'bun:test'
+import React from 'react'
+import stripAnsi from 'strip-ansi'
+
+import { AppStateProvider } from '../state/AppState.js'
+import { createRoot } from '../ink.js'
+import { KeybindingSetup } from '../keybindings/KeybindingProviderSetup.js'
+import { ConsoleOAuthFlow } from './ConsoleOAuthFlow.js'
+
+const SYNC_START = '\x1B[?2026h'
+const SYNC_END = '\x1B[?2026l'
+
+function extractLastFrame(output: string): string {
+  let lastFrame: string | null = null
+  let cursor = 0
+
+  while (cursor < output.length) {
+    const start = output.indexOf(SYNC_START, cursor)
+    if (start === -1) {
+      break
+    }
+
+    const contentStart = start + SYNC_START.length
+    const end = output.indexOf(SYNC_END, contentStart)
+    if (end === -1) {
+      break
+    }
+
+    const frame = output.slice(contentStart, end)
+    if (frame.trim().length > 0) {
+      lastFrame = frame
+    }
+    cursor = end + SYNC_END.length
+  }
+
+  return lastFrame ?? output
+}
+
+function createTestStreams(): {
+  stdout: PassThrough
+  stdin: PassThrough & {
+    isTTY: boolean
+    setRawMode: (mode: boolean) => void
+    ref: () => void
+    unref: () => void
+  }
+  getOutput: () => string
+} {
+  let output = ''
+  const stdout = new PassThrough()
+  const stdin = new PassThrough() as PassThrough & {
+    isTTY: boolean
+    setRawMode: (mode: boolean) => void
+    ref: () => void
+    unref: () => void
+  }
+
+  stdin.isTTY = true
+  stdin.setRawMode = () => {}
+  stdin.ref = () => {}
+  stdin.unref = () => {}
+  ;(stdout as unknown as { columns: number }).columns = 120
+  stdout.on('data', chunk => {
+    output += chunk.toString()
+  })
+
+  return {
+    stdout,
+    stdin,
+    getOutput: () => output,
+  }
+}
+
+async function renderFrame(node: React.ReactNode): Promise<string> {
+  const { stdout, stdin, getOutput } = createTestStreams()
+  const root = await createRoot({
+    stdout: stdout as unknown as NodeJS.WriteStream,
+    stdin: stdin as unknown as NodeJS.ReadStream,
+    patchConsole: false,
+  })
+
+  root.render(
+    <AppStateProvider>
+      <KeybindingSetup>{node}</KeybindingSetup>
+    </AppStateProvider>,
+  )
+
+  await Bun.sleep(50)
+  root.unmount()
+  stdin.end()
+  stdout.end()
+  await Bun.sleep(25)
+
+  return stripAnsi(extractLastFrame(getOutput()))
+}
+
+test('login picker shows the third-party platform option', async () => {
+  const output = await renderFrame(<ConsoleOAuthFlow onDone={() => {}} />)
+
+  expect(output).toContain('Select login method:')
+  expect(output).toContain('3rd-party platform')
+})
+
+test('third-party provider branch opens the provider wizard', async () => {
+  const output = await renderFrame(
+    <ConsoleOAuthFlow
+      initialStatus={{ state: 'platform_setup' }}
+      onDone={() => {}}
+    />,
+  )
+
+  expect(output).toContain('Set up a provider profile')
+  expect(output).toContain('OpenAI-compatible')
+  expect(output).toContain('Ollama')
+})