[PATCH v2 0/5] docs(l10n): AI agent instructions and workflow improvements

## Introduction

This series introduces AI agent instructions for Git localization (l10n) workflows to help localization contributors quickly complete drafts and use AI to check translation quality. The changes focus on:

1. Separating agent-specific documentation into po/AGENTS.md for targeted
   optimization of AI-assisted workflows
2. Providing step-by-step instructions for update-pot, update-po, translation,
   and review tasks
3. Simplifying location filtering for PO file commits via .gitattributes

AI-assisted translation is optional; many successful l10n teams work well without it. When used, AI output serves as reference only—human contributors must review and approve before submission.

## Performance summary

| Task        | Before        | After        | Improvement                     |
|-------------|---------------|--------------|---------------------------------|
| update-pot  | 17 turns, 34s | 3 turns, 8s  | -82% turns, -76% time           |
| update-po   | 22 turns, 38s | 4 turns, 9s  | -82% turns, -76% time           |
| translate   | 86 turns      | 56 turns     | -35% turns (git-po-helper flow) |
| review      | N/A           | 96/100 score | New workflow documented         |

These improvements reduce API costs and make agent workflows more efficient while maintaining human oversight of translation quality.

## Testing

All changes have been evaluated with the qwen model via git-po-helper agent-test and agent-run. The po/AGENTS.md instructions are designed to work with coding tools that support file references (e.g., "Translate po/zh_CN.po by referring to @po/AGENTS.md").

## Changes

Jiang Xin (5):
  l10n: add .gitattributes to simplify location filtering
  docs(l10n): add AGENTS.md with optimized update-pot instructions
  docs(l10n): add AI agent instructions for updating po/XX.po files
  docs(l10n): add AI agent instructions for translating PO files
  docs(l10n): add AI agent instructions to review translations

 po/.gitattributes |  36 ++
 po/AGENTS.md      | 941 ++++++++++++++++++++++++++++++++++++++++++++++
 po/README.md      |  70 ++--
 3 files changed, 1015 insertions(+), 32 deletions(-)
 create mode 100644 po/.gitattributes
 create mode 100644 po/AGENTS.md