docs(autofix): update Autofix description and add coding agent handoff section (#17366)

## Summary

Two docs changes to surface coding agent handoff in the Autofix flow:

### 1. `docs/ai/index.mdx`

Updated the **Seer - Autofix** card description from:
> Find root causes and get code fixes for your issues, powered by Seer.

To:
> Automatically root cause any issue and generate fixes with Seer,
Claude Code, Cursor Cloud Agents, or Copilot.

### 2. `docs/product/ai-in-sentry/seer/autofix/index.mdx`

Added a new subsection **"Handoff to Claude Code, Cursor Cloud Agents,
or Copilot"** under **How Issue Autofix Works > Code Generation**,
covering:
- What coding agent handoff is and when to use it
- Supported agents: Claude Code, Cursor Cloud Agents, GitHub Copilot —
with a brief description of how each integration works
- How to enable it via Integrations settings

Also updated the step 3 summary line in the flow overview to mention the
coding agent handoff option.

Requested by <@URCU7R7U2>

---------

Co-authored-by: Junior <junior@sentry.io>
Co-authored-by: Rahul Chhabria <rahul.chhabria@sentry.io>
Co-authored-by: Claude <noreply@anthropic.com>

Author: 4 people

docs/ai/index.mdx

@@ -69,7 +69,7 @@ Looking for Sentry's AI-powered debugging features? Sentry uses AI to help you d
     href="/product/ai-in-sentry/seer/autofix/"
     iconSrc="/ai/img/IconSeer.svg"
     title="Seer - Autofix"
-    description="Find root causes and get code fixes for your issues, powered by Seer."
+    description="Automatically find the root cause of any issue and generate fixes with Seer, Claude Code, Cursor Cloud Agents, or Copilot."
     className="w-full md:w-[calc(50%-12px)]"
   />
   <LinkCard

docs/product/ai-in-sentry/seer/autofix/index.mdx

@@ -38,7 +38,7 @@ Seer's Issue Autofix flow follows a three step process:
 
 1. [Root Cause Analysis](#root-cause-analysis): Analyze the issue using Sentry's context and your codebases and determine the root cause
 2. [Solution Identification](#solution-identification): Identify a solution based on the analysis
-3. [Code Generation](#code-generation): Generate a code fix and (optionally) open a PR
+3. [Code Generation](#code-generation): Generate a code fix and (optionally) open a PR, or hand off to a coding agent
 
 You can always manually trigger the Autofix flow from the Issue Details page. Issues will automatically trigger the flow when an agent is configured for background handoff and the Issue is highly actionable with 10+ events captured and high medium or above fixability score.
 
@@ -83,6 +83,22 @@ snippets and examples, and does not affect workflows involving your own coding a
 
 ![Screenshot of Seer showing code it generated =800x](../img/coding-step.png)
 
+### Handoff to Claude Code, Cursor Cloud Agents, or Copilot
+
+Seer always performs root cause analysis and solution planning using its own internal tools and Sentry context. At the final code generation step, instead of having Seer generate the code fix directly, you can hand off to an external coding agent for implementation. Seer passes along the root cause and solution plan so the coding agent can act on them. This lets you leverage the strengths of specialized code generation tools while still benefiting from Seer's debugging and analysis.
+
+Supported coding agents for handoff:
+
+- **Claude Code** — Seer passes the root cause and solution as a structured prompt that Claude Code can act on directly in your terminal or CI environment.
+- **Cursor Cloud Agents** — Seer triggers a Cursor Cloud Agent to implement the fix asynchronously, without requiring your local IDE to be open.
+- **GitHub Copilot** — Seer opens a GitHub issue or PR with the full context, which Copilot can then pick up and implement.
+
+To enable coding agent handoff, connect a coding agent integration in [Integrations settings](https://sentry.io/orgredirect/organizations/:orgslug/settings/integrations/?category=coding%20agent). Once connected, the handoff option will appear at the Code Generation step of the Autofix flow, alongside the standard "Create PR" and "Checkout locally" options.
+
+<Alert>
+Coding agent integrations handle their own authentication and repository access. Make sure the agent can access the same repositories connected to your Sentry project.
+</Alert>
+
 ## Autofix in Slack
 
 <Alert>