feat(ui): redesign voice cockpit with clinical companion drawer, Svelte 5 migration, and Gemini 3.8 voice

- Re-architect VoiceSession into full-bleed studio cockpit with overlay slide-over companion drawer
- Eliminate width squishing defect on LiveInsightPanel and add native dark/light theme support
- Integrate authentic Google Gemini 3.8 Flash TTS with Fenrir persona and fallback audio pipeline
- Implement comprehensive Playwright E2E visual regression suite across Desktop, iPad, and iPhone (21 tests, 45 snapshots)
- Migrate core application to Svelte 5 runes (, , ) with reactive stores
- Maintain .NET 8 Azure Functions serverless endpoints and clean build hygiene

GEMINI.md

@@ -0,0 +1,16 @@
+# GEMINI.md - Cognitive Clarity Architectural Rules
+
+This repository defines the **Cognitive Clarity** adaptive clinical simulation system.
+
+---
+
+## Autonomous Agent Invariants
+
+1. **OpenRouter Exclusive Execution**: All AI operations (text dialogue streaming, clinical turn analysis, scenario generation, and vocal speech synthesis) MUST route exclusively through OpenRouter API (`https://openrouter.ai/api/v1`). Direct Google API keys or endpoints are strictly forbidden.
+2. **Strict Character Boundaries**: AI roleplay characters must NEVER provide clinical meta-commentary, congratulations, or diagnostic advice within dialogue turns. Feedback is handled asynchronously by the supervisor engine.
+3. **Audio Stream Integrity**: WebAudio processing must properly manage WebAudio Context lifecycles, avoid main-thread blocking, and drive FFT visualizer states accurately.
+4. **C# Isolated Functions Parity**: Ensure `api/api.csproj` builds cleanly with .NET 8, maintaining type fidelity with TypeScript schemas in `types.ts` and consuming OpenRouter via `HttpClientFactory`.
+5. **Zero Residual Slop**: Temporary scripts or exploratory files must be placed in `scripts/` or scratch directories and never committed in a broken state.
+6. **Continuous Changelog**: Every feature, bugfix, or architectural update must be recorded in `CHANGELOG.md`.
+
+Refer to [AGENTS.md](file:///Users/moo/Development/Repositories/clarity-helper/AGENTS.md) for full workspace specifications.