[Meeting Intelligence] Implement Flutter-Native Platform Channel Contracts

[ucguy4u]

Problem

Airo needs defined Flutter-to-Native interfaces for recording and transcribing meetings on-device.

Scope

• Define platform channels com.airo.meeting/recorder and com.airo.meeting/transcription.
• Create domain models (MeetingRecord, MeetingSegment, TranscriptChunk).
• Create an in-memory repository for unit testing and UI scaffolding.

Acceptance Criteria

• Platform channel method calls are defined with strict types.
• Unit tests pass using the in-memory mock repository.

Estimate

5 hours

[ucguy4u]

Required Before Implementation: Use Cases + Automation Flow

Before coding this ticket, add a deterministic implementation note or child task covering:

• Primary user journey: actor, preconditions, trigger, happy path, success state.
• Alternate/failure paths: offline, missing model, permission denied, runtime/tool failure, cancel/retry, background/foreground.
• Automation flow: Given/When/Then steps, fixtures, mocks/stubs, UI assertions, state/database assertions, notification/tool-trace/memory assertions where relevant.
• Hardening checks: privacy redaction, accessibility, timeout/performance bounds, cleanup/reset.
• Delegation prompt: Ask a QA/test agent to write the automation flow before implementation begins.

Tracker: #323

[ucguy4u]

Critical Agent Gate

Problem: Airo needs a deterministic Flutter-to-native contract layer for meeting recording/transcription before platform-specific recorder implementations land.
User / actor: Meeting Intelligence Agent, Mobile UI Agent, and QA automation working on Live Notes foundations.
Framework or application layer: Framework.
Owning agent: Framework Agent.
Reviewing agents: Meeting Intelligence Agent, Mobile UI Agent, QA Automation Agent.
Impacted modules/files: app/lib/features/meeting/domain/entities/*, app/lib/features/meeting/infrastructure/*, app/test/features/meeting/*, native platform channel registration surfaces if needed.
Base branch/worktree: confirmed from latest origin/main: yes.
Open questions: Whether current MeetingRecord/TranscriptChunk shapes satisfy the original issue without reintroducing deprecated models; whether native registration needs stubs in this ticket or can stay in the follow-up Android/iOS integration tickets.
Decision: Ready

Deterministic Use Cases

1. Recorder contract bootstrap

• Actor: Flutter meeting feature.
• Preconditions: app booted, no active meeting.
• Trigger: feature starts a local meeting recording.
• Happy path: recorder channel receives a strict typed payload and returns a typed result with meeting/audio metadata.
• Success state: Flutter receives a valid MeetingRecord/audio payload without dynamic map leakage beyond the contract boundary.

2. Transcription contract bootstrap

• Actor: Flutter meeting feature.
• Preconditions: active meeting id exists.
• Trigger: feature starts realtime transcription.
• Happy path: transcription channel receives typed start args, stream emits typed TranscriptChunk events, stop call completes.
• Success state: transcript events are parsed into deterministic domain objects.

3. Failure path

• Actor: Flutter meeting feature.
• Preconditions: native layer returns malformed payload or wrong field types.
• Trigger: recorder/transcription response parsing.
• Failure behavior: contract rejects the payload with deterministic parsing errors rather than silently accepting invalid shapes.

Automation Flow

Given a mocked method/event channel
When Flutter starts recorder or transcription flows
Then the exact channel names, method names, and typed argument maps are asserted
And malformed payloads fail deterministically
And in-memory meeting repository tests still pass for local scaffolding coverage.

Hardening Checks

• Strict payload parsing with explicit required fields and numeric coercion rules.
• No persistence or native side effects required for unit tests.
• Keep contract layer isolated from UI to avoid accidental cross-boundary coupling.