fix: prevent PR targeting same branch and duplicated prefix

[rubenmarcus]

Summary

• Use default branch (main/master) as PR base for the first task, instead of originalBranch which could be an auto/* branch from a previous run
• Add getDefaultBranch() helper that detects main/master via git symbolic-ref with fallback
• Strip existing conventional commit prefix from task title to prevent duplicated feat: feat: in PR titles

Root Cause

When auto mode runs on a branch that's already auto/github-1, the first PR would target auto/github-1 as both head and base, causing "No commits between X and X" error.

Test plan

• Run ralph-starter auto from main branch — first PR should target main
• Run ralph-starter auto from an auto/* branch — first PR should still target main/master
• Verify PR titles don't have duplicated prefixes like feat: feat:

Closes #208

🤖 Generated with Claude Code

[github-actions]

✔️ Bundle Size Analysis

Metric	Value
Base	1848.54 KB
PR	1850.48 KB
Diff	1.93 KB (0%)

Bundle breakdown

156K	dist/auth
32K	dist/automation
4.0K	dist/cli.d.ts
4.0K	dist/cli.d.ts.map
16K	dist/cli.js
12K	dist/cli.js.map
460K	dist/commands
28K	dist/config
4.0K	dist/index.d.ts
4.0K	dist/index.d.ts.map
4.0K	dist/index.js
4.0K	dist/index.js.map
536K	dist/integrations
84K	dist/llm
728K	dist/loop
172K	dist/mcp
32K	dist/presets
92K	dist/setup
36K	dist/skills
392K	dist/sources
76K	dist/ui
84K	dist/utils
336K	dist/wizard

[greptile-apps]

Greptile Summary

Fixes PR creation bug where auto mode would target the same branch as both head and base when running from an existing auto/* branch. Also prevents duplicate conventional commit prefixes in PR titles.

Key changes:

• Added getDefaultBranch() helper that uses git symbolic-ref to detect main/master with proper fallbacks
• First PR now targets the repository's default branch instead of originalBranch (which could be an auto/* branch)
• PR titles strip existing conventional commit prefixes to prevent feat: feat: duplicates
• The prefix regex is comprehensive, covering all 9 conventional commit types

Note: The prefix-stripping regex on line 164 is more comprehensive (9 types) than the one in buildCommitMessage() on line 272-273 (6 types). Consider unifying these patterns for consistency.

Confidence Score: 4/5

• This PR is safe to merge with minor inconsistency to address
• The implementation correctly solves the root cause of the PR creation bug and adds proper fallback logic. The getDefaultBranch() function is well-designed with multiple fallback mechanisms. However, there's a minor style inconsistency between the prefix-stripping regex patterns used in different parts of the code that should be unified for maintainability.
• No files require special attention - the changes are straightforward and well-contained

Important Files Changed

Filename	Overview
src/automation/git.ts	Added getDefaultBranch() helper to detect main/master branch via git symbolic-ref with fallback logic
src/loop/task-executor.ts	Fixed PR base branch targeting to use default branch and prevented duplicate conventional commit prefixes in PR titles

_{Last reviewed commit: 3c3d632}

[greptile-apps]

_{2 files reviewed, 1 comment}

_{Edit Code Review Agent Settings | Greptile}

[chatgpt-codex-connector]

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[chatgpt-codex-connector]

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Reviewed commit: 04e39e6225

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