Add ARB 4-space indent guard to pre-commit hook

[beastoin]

Closes the gap that let PR #5268 balloon to ~98K lines from editor reformatting ARB files.

• Pre-commit hook now detects 2-space-indented ARB files and auto-fixes them to 4-space via jq.
• app/.editorconfig tells editors to use 4-space indent for *.arb / *.json by default.

---

by AI for @beastoin

[beastoin]

lgtm

[greptile-apps]

Greptile Summary

This PR adds guardrails to prevent ARB localization files from being reformatted with 2-space indent. It introduces an .editorconfig to set editor defaults and a pre-commit hook to detect and auto-fix incorrectly indented files.

Key Changes:

• Added app/.editorconfig to enforce 4-space indent for *.arb and *.json files
• Added pre-commit validation to detect 2-space indented ARB files and reformat with jq --indent 4

Critical Issue:

• The detection logic on line 35 has a bug that prevents it from catching 2-space indented ARB files with nested objects (which most ARB files have). ARB files contain metadata entries like @key with nested description fields, meaning a 2-space file would have both 2-space lines (level 1 keys) and 4-space lines (level 2 nested keys). The condition && ! grep -qP '^\s{4}"' causes the check to fail for these common cases.

Confidence Score: 1/5

• This PR has a critical logic bug that prevents it from achieving its stated goal
• The pre-commit hook won't actually prevent the problem it's designed to solve. The detection logic fails for ARB files with nested structure (which is standard), meaning 2-space indented files would pass through undetected. This defeats the entire purpose of PR Add ARB 4-space indent guard to pre-commit hook #5273.
• scripts/pre-commit requires immediate attention - line 35 needs the logic fix suggested in the inline comment

Important Files Changed

Filename	Overview
scripts/pre-commit	adds ARB indent validation but logic fails to detect 2-space files with nesting
app/.editorconfig	configures editors to use 4-space indent for ARB/JSON files

_{Last reviewed commit: 8faa1ab}

[greptile-apps]

_{2 files reviewed, 1 comment}

_{Edit Code Review Agent Settings | Greptile}

[greptile-apps]

this logic won't detect 2-space indented ARB files with nested objects. ARB files have metadata like @key with nested description fields, so a 2-space file would have lines with both 2 spaces (level 1) and 4 spaces (level 2). the condition fails because ! grep -qP '^\s{4}"' returns false

Suggested change

	if grep -qP '^\s{2}"' "$f" && ! grep -qP '^\s{4}"' "$f"; then
	if grep -qP '^\s{2}"' "$f"; then