Add OpenAI ChatGPT Plus/Pro provider documentation

docs/providers/index.json

@@ -126,6 +126,12 @@
       "extension": true,
       "cloud": true
     },
+    {
+      "id": "providers/openai-chatgpt-plus-pro",
+      "title": "OpenAI ChatGPT Plus/Pro",
+      "extension": true,
+      "cloud": true
+    },
     {
       "id": "providers/openai-compatible",
       "title": "OpenAI Compatible",

docs/providers/openai-chatgpt-plus-pro.mdx

@@ -0,0 +1,60 @@
+---
+sidebar_label: OpenAI ChatGPT Plus/Pro
+description: Connect your OpenAI ChatGPT Plus or Pro subscription directly to Roo Code through OAuth authentication. No API keys needed.
+keywords:
+  - openai
+  - chatgpt plus
+  - chatgpt pro
+  - oauth
+  - roo code
+  - subscription
+  - no api key
+  - browser authentication
+---
+
+# OpenAI ChatGPT Plus/Pro Provider
+
+This provider connects Roo Code to OpenAI's models through your ChatGPT Plus or Pro subscription. Authentication uses OAuth, so no API keys are required. Usage counts against your subscription instead of separate API billing.
+
+<div style={{width: '50%', margin: 'auto'}}>
+  <div style={{position: 'relative', paddingBottom: '177.77%', height: 0, overflow: 'hidden'}}>
+    <iframe
+      src="https://www.youtube.com/embed/t0sIT8nGvrk"
+      title="OpenAI ChatGPT Plus/Pro Provider Setup Tutorial"
+      frameBorder="0"
+      allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture"
+      allowFullScreen
+      style={{position: 'absolute', top: 0, left: 0, width: '100%', height: '100%'}}
+    ></iframe>
+  </div>
+</div>
+
+---
+
+## Setup
+
+1. Create a new API configuration profile in Roo Code settings.
+2. Choose "OpenAI - ChatGPT Plus/Pro" from the provider dropdown.
+3. Click "Sign In" to open your browser for authentication.
+4. Sign in to your OpenAI account when prompted.
+
+<img src="/img/openai-chatgpt-plus-pro/setup.png" alt="OpenAI ChatGPT Plus/Pro provider selection in Roo Code settings" width="600" />
+
+Once authenticated, you're connected. The OAuth token refreshes automatically, so you won't need to sign in again unless you explicitly sign out.
+
+---
+
+## Available Models
+
+Model availability depends on your ChatGPT Plus or Pro subscription tier. The provider uses the models available to your account through the ChatGPT web interface.
+
+For current model access based on subscription type, see [OpenAI's ChatGPT plans](https://openai.com/chatgpt/pricing).
+
+---
+
+## Tips and Notes
+
+* **Subscription Required:** You need an active ChatGPT Plus or Pro subscription. This provider won't work with free ChatGPT accounts.
+* **No API Costs:** Usage through this provider counts against your ChatGPT subscription, not separately billed API usage.
+* **Sign Out:** To disconnect, use the "Sign Out" button in the provider settings.
+* **Alternative:** If you prefer direct API access with pay-per-use billing, see the [OpenAI provider](/providers/openai) instead.