[agency] Create CLJS conversation orchestrator over typed agency events

[meekmachine]

Goal

Create the Polyester conversation agency as a ClojureScript orchestrator over typed TTS, transcription, gaze, blink, prosodic, vocal/lipsync, and emotion-expression events.

Current state

Polyester root still inherits the TypeScript conversation service from Latticework. There is no src-cljs/latticework/conversation.cljs agency yet. LoomLarge discussions indicate the LiveKit path is the strongest current showpiece base, while older generic conversation scaffolding was removed or de-emphasized.

Relevant references:

• Latticework issue: Rewrite conversation agency as CLJS worker-backed orchestrator Latticework#39
• LoomLarge issue: meekmachine/LoomLarge#229
• LoomLarge discussion: meekmachine/LoomLarge#497
• LoomLarge discussion noting module-owned / LiveKit-specific direction: meekmachine/LoomLarge#338

Clojure-way direction

• CLJS owns turn state, speaking/listening/thinking/interrupted state, interruption policy, pending transcript handling, social-motion intent, and command generation.
• Other agencies expose typed command/event surfaces; conversation does not hold service instances or mutate Loom3 directly.
• Host/module adapters own backend connections, LiveKit rooms, browser APIs, and UI state.
• The first target should be one coherent LiveKit-first showpiece path, then adapters for AI Chat/French Quiz if the contract holds.

Acceptance criteria

• Existing createConversationService imports remain compatible through an adapter or documented replacement path.
• Conversation state snapshots are serializable and can be emitted from worker or in-process CLJS.
• Interruption stops audio and visible speaking motion without stale mouth/gaze/prosody snippets.
• Speaking/listening/thinking/interrupted states emit coordinated commands for gaze, blink, prosodic, vocal/lipsync, and emotion expression.
• Current conversation tests pass, especially interruption orchestration.
• Add CLJS tests for turn lifecycle, final transcript handling, interruption, command ordering, and cleanup.
• Worker code has no browser API, backend client, LiveKit room, DOM, Loom3, or service-instance references.