fix: read issue comments for full context (#1237)

## Summary

Explicitly instruct the agent to read issue comments via `gh issue view
--comments`, not just the issue body. Important context is often in
comments.

## Test plan

- [ ] Add `ambient-code:auto-fix` to an issue with context in comments —
verify agent reads them

🤖 Generated with [Claude Code](https://claude.com/claude-code)

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

## Summary by CodeRabbit

* **Chores**
* Enhanced issue handling workflow to ensure comprehensive context
reading by requiring review of issue body and all comments before
processing.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

Co-authored-by: Ambient Code Bot <bot@ambient-code.local>
Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: 3 people

.github/workflows/amber-issue-handler.yml

@@ -82,7 +82,7 @@ jobs:
 
             ## Instructions
 
-            1. Read the issue and understand the problem.
+            1. Read the issue body and all comments for full context (`gh issue view --comments`).
             2. Explore the codebase to find the relevant code.
             3. Create a plan for how to fix the issue. If there is any ambiguity —
                unclear requirements, multiple valid approaches, missing context — you
@@ -275,7 +275,7 @@ jobs:
 
             ## Instructions
 
-            1. Read the issue and understand the problem.
+            1. Read the issue body and all comments for full context (`gh issue view --comments`).
             2. Explore the codebase to find the relevant code.
             3. Create a plan for how to fix the issue. If there is any ambiguity —
                unclear requirements, multiple valid approaches, missing context — you