Motivation

• CI for downstream projects reported failures complaining about mapfile: command not found, which is caused by using the Bash-4+ builtin mapfile on runners that have older Bash (notably macOS Bash 3.2) or minimal shells.
• The goal is to avoid Bash-version-specific builtins so the action runs reliably on a wider set of GitHub runners.

Description

• Replaced mapfile -t TARGET_PATHS < <(printf '%s' "$TARGETS") with a portable while IFS= read -r TARGET_PATH || [[ -n "$TARGET_PATH" ]] loop that appends to TARGET_PATHS.
• Replaced mapfile -t CHANGED_FILES < <(git diff --name-only ... ) with a while IFS= read -r CHANGED_FILE || [[ -n "$CHANGED_FILE" ]] loop that fills CHANGED_FILES from process substitution.
• Applied the same TARGETS parsing change in the git commit step so both the git-status and git-commit steps no longer rely on mapfile.
• Kept quoting, array handling, and empty-line semantics intact to preserve original behavior.

Testing

• Ran rg -n "mapfile" action.yml and confirmed there are no remaining mapfile usages (success).
• Ran git diff --stat HEAD~1..HEAD to verify the expected changes were produced to action.yml (success).
• Ran git status --short and inspected action.yml with nl -ba action.yml | sed -n ... to validate the replacements are in the intended locations (success).

Codex Task