v0.9.0 — Newsletter system admin UI

Newsletter system admin UI (Wave 0)

The shared Vue/Inertia frontend now ships the full newsletter admin surface, consumed identically by every Escalated backend.

Added

• Newsletter admin UI — compose / index / show pages, deliveries table, analytics tiles, dynamic segment-filter builder, list-member table, markdown editor, merge-field dropdown, preview iframe (+ Storybook stories). (#75)
• usePermissions() composable + permission-gated admin nav — the newsletter entry renders only for users with newsletters.manage, matching backend enforcement. (#96)
• Central translations consumed from @escalated-dev/locale; local src/locales/*.json win as overrides.

Changed

• Newsletter admin pages wired to locale strings (i18n). (#96)

Full Changelog: v0.8.0...v0.9.0