The hook installers fell back to settings={} on any JSON parse error and
then overwrote the whole file, destroying the user's config (the likely
trigger is a UTF-8 BOM, same class as #2163). All four installers now
read utf-8-sig, refuse to modify a file that isn't a JSON object (naming
the path) instead of clobbering it, back up to <name>.graphify-bak before
any modifying write, skip the write when content is unchanged, and guard
the PreToolUse filter against non-dict entries.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
