feat(ios): build inbox search conversations and actions

[Tutitoos]

Plan reference

Post-1.0 — iPhone and iPad: core mail experience.

Objective

Deliver adaptive native inbox, account folders, categories, search, conversation reading, and optimistic actions using server contracts and the offline cache.

Scope

• Build iPhone stack and iPad split navigation, virtualized lists, account switching, categories, search operators, safe HTML mail rendering, remote-image control, pull to refresh, selection, swipe and bulk actions, offline and resync states.

Tasks

• Define Swift 6 models, actors, storage, API, and UI boundaries for this scope.
• Implement the smallest complete native capability.
• Add XCTest, Swift Concurrency, migration, UI, accessibility, and device tests where applicable.
• Update generated clients, translations, privacy declarations, and distribution documentation.

Acceptance criteria

• Gmail, Microsoft, and IMAP accounts display without cross-account thread merging.

• Search supports the documented operators and respects offline availability.

• Remote content remains blocked by default and unsafe HTML cannot escape isolation.

• Actions are idempotent, accessible, localized, and reconcile after offline use.

• Account isolation, data protection, accessibility, EN default, and ES completeness match the web and macOS contracts.

• Tokens, credentials, message content, recipients, and personal data never enter logs, crash reports, screenshots, fixtures, URLs, or notification defaults.

• The capability is independently reviewable and rollback-safe.

Validation

• Run reducer or view-model, cache, generated client, HTML security, VoiceOver, Dynamic Type, iPhone, iPad, offline, rotation, and provider E2E tests.

• Run Swift build, XCTest, strict concurrency checks, generated-client diff, and the affected simulator and physical-device UI tests.

• Use sanitized fixtures and protected accounts only for final manual provider validation.

Dependencies

Post-1.0 work. Blocked until Mailflow 1.0.0 is released: https://github.com/Tutitoos/mailflow/milestone/9

Risks

Offline state, background execution, notification privacy, generated contracts, and device credentials can diverge from server truth. Use actors, Keychain, bounded caches, explicit conflict states, and real-device validation.

Out of scope

• Composer, attachments, APNs, widgets, calendar, and post-1.0 productivity features.