N02: Deliver scalable topic and direct-token fanout

[TheDarkSkyXD]

Parent

Build StreamFusion Mobile for Android

What to deliver

Versioned preference projection reconciliation, stable channel topics, one-mode event delivery, private direct tokens, 2,000-topic overflow, retries, and invalid-token retirement.

Capability IDs

• notifications

Code ownership

• relay
• mobile
• core

Acceptance criteria

• The behavior above works through the real Android application or the named verification/release path; code presence alone is insufficient.
• Each affected capability has an updated Android Parity Record bound to the current Desktop Baseline and Android candidate.
• The implementation respects the approved responsibility layers and adapter boundaries owned by this ticket.
• Required evidence is indexed: change-gate, relay-contract-tests, topic-delivery, direct-delivery, topic-overflow, deduplication.
• External, lifecycle, persistence, native, or release boundaries define and verify safe failure containment, retry, fallback, disablement, rollback, or forward-fix behavior as applicable.
• The normal Change Gate passes with no untracked architecture exception, quarantined required test, or Development Exception.

Blocked by

• N01: Register native FCM delivery and present notifications

Sources

• Approved implementation specification
• Approved implementation roadmap
• Machine-readable ticket graph

Feature-owned UI and UX acceptance

User direction recorded 2026-09-07: this issue delivers its complete UI and UX together with its behavior. Do not defer feature UI to #195, parity closure, or a release issue. PRD section 6.7 and the normative screen and control contract apply.

Specific UI/integration scope: Delivery failures, reconciliation status and direct/topic/overflow outcomes exposed at existing Activity/Settings/Diagnostics consumers. No new delivery dashboard or secrets.

• Map the affected PRD/source decisions, mockup scenarios, screens, tabs, components, controls and business rules to this issue's implementation and tests.
• Implement the complete approved hierarchy, visual design and real interactions. No placeholder pages, inert buttons, mock-only outcomes or deferred required controls.
• Complete applicable loading, empty, partial, stale/offline, error/retry, busy/disabled, signed-out/auth-lost, permission, constrained and unsupported states. Include cancellation, repeated actions, lifecycle recovery and persistence feedback.
• Verify portrait navigation, safe areas, keyboard/search/sheet/mini-player clearance, long content, supported resizing, 48dp targets, large text, contrast and semantic accessibility in actual usages.
• Test the real Android feature using root npm start option 3 and Mobile MCP. Use the matching development client for custom native behavior. Attach matched mockup/app screenshots, observed actions and failure/recovery evidence, source/artifact identity and regression results.
• Resolve this feature's UI/UX findings before closing. Keep specified, implemented and verified status separate. An evidence or design gap stays open; linking a later ticket is not completion.

Infrastructure-only work must identify its real consumer, verify changed consumer states and justify any no-new-UI claim. Native/backend implementation alone does not exempt a user-facing feature. #195 reviews consistency continuously and completes integrated review before #178 promotion.

• Compare the current Desktop screen, controls, menus/context actions, settings, business rules, states and tests with this Mobile feature. Deliver every outcome through a mobile-ready interaction or a specifically approved Android adaptation. Add missing mockup/PRD content within this feature; the mockup is not a reduced feature list. Verify Desktop-to-Mobile results before closure. Binding PRD clarification.