[FEATURE] Enable custom branch naming workflows on GitHub Claude app

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

Our team has our own branch naming convention for PRs, but using @claude on GitHub fails to abide by these rules, even when listed in Claude.md, AGENTS.md, etc. Claude itself diagnosed it as something not fixable without an update to the Claude Code GitHub app, which appears to hardcode a issue#-and-date branch name format for Claude's automatic PR generations (with PR write permissions granted --- not talking about the 'Create PR' hyperlinks [though maybe the problem is there as well, but we try not to use those links as they are fragile and instead gave Claude permission to directly create PRs]).

Proposed Solution

Enable .github/workflow override of Claude's branch naming for PR generation.

(Or if that already exists, make sure that @Claude itself can instruct about how to accomplish this.)

Alternative Solutions

Tried to ask @Claude how to fix it, and Claude said it can't be fixed -- only if Anthropic updates its GitHub app.

Priority

Medium - Would be very helpful

Feature Category

Configuration and settings

Use Case Example

We're currently making PR branches with the PR# and a short semantic description of the PR's purpose, but instead Claude only makes the branch name with the issue# and the date.

Additional Context

_No response_