v0.7.4

Tooling (no SDK behaviour change)

Phase 4 of the Track F + test-coverage audit hardening pass. The
published artefact is functionally identical to 0.7.3; only the
build / CI tooling and CHANGELOG differ.

• Bundle-size budgets (F6). size-limit is wired into CI with
  per-entry-point budgets defined in package.json:

  Entry point	Budget
  @dojocoding/whatsapp (root, ESM/CJS)	100 KB
  @dojocoding/whatsapp/express	6 KB
  @dojocoding/whatsapp/web	3 KB
  @dojocoding/whatsapp/hono	3 KB
  @dojocoding/whatsapp/storage/redis	2 KB
  @dojocoding/whatsapp/storage/postgres	4 KB

  Limits are roughly 1.5× the current measured sizes, so a single PR
  cannot double a bundle by accident (e.g. an accidental
  import "lodash"). Run pnpm size locally to see the same
  budget report CI runs.