v2.7.2 — auto-migrate legacy config.json on --force install

Patch release. Fixes the lingering pre-v2.6 → v2.7 config filename mismatch.

What changed:
  - cursor-install.sh auto-detects haze-wiki/config.json (legacy name),
    renames to haze-config.json (canonical), backs up as
    config.json.legacy-bak, then jq-merges existing values with v2.7.2
    defaults. Existing settings preserved. Version bumped explicitly.
  - Hook lib scripts (debug-log.sh, capture-transcript.sh) try both
    filenames, so legacy installs without --force re-run keep working.

Canonical hashes:

  install.sh sha256:        99fa1ae824ff9f634a025b6a593839a878844309434ab5fdc3cb0037a373204c
  cursor-install.sh sha256: 65e336ab6f073ee81db7941a5ae566c53755cf5e9249f0eb4decdaf1e9c921d6

Migration check after re-running --force:
  /haze status  →  '=== Wiki Status (v2.7.2) ===' (no more pre-v2.7 warning)
  ls haze-wiki/  →  haze-config.json present; config.json.legacy-bak present