# Issue #43: Display Inference Statistics in Chat UI

**Status:** IMPLEMENTING
**Issue:** [#43](https://git.shahondin1624.de/llm-multiverse/llm-multiverse-ui/issues/43)
**Branch:** `feature/issue-43-inference-stats`

## Overview

Add a collapsible UI panel that displays LLM inference statistics (token counts, context window utilization, throughput) below assistant messages after orchestration completes.

## Phases

### Phase 1: Proto Types

**Files:**
- `proto/upstream/proto/llm_multiverse/v1/common.proto` — Add `InferenceStats` message
- `proto/upstream/proto/llm_multiverse/v1/orchestrator.proto` — Add optional `inference_stats` field to `ProcessRequestResponse`

**InferenceStats message fields:**
- `prompt_tokens` (uint32) — tokens in the prompt
- `completion_tokens` (uint32) — tokens generated
- `total_tokens` (uint32) — sum of prompt + completion
- `context_window_size` (uint32) — model's maximum context length
- `tokens_per_second` (float) — generation throughput

**Then regenerate types:** `npm run generate`

### Phase 2: Orchestration State

**Files:**
- `src/lib/composables/useOrchestration.svelte.ts` — Extract `inferenceStats` from response, expose via store getter

### Phase 3: InferenceStatsPanel Component

**Files:**
- `src/lib/components/InferenceStatsPanel.svelte` — New component

**Design:**
- Follow `<details>` pattern from FinalResult.svelte
- Collapsed by default
- Summary line shows key stat (e.g., total tokens + tokens/sec)
- Expanded content shows all stats in a grid layout
- Context utilization shown as a progress bar
- Blue/indigo color scheme (neutral, info-like)
- Full dark mode support

### Phase 4: Chat Page Integration

**Files:**
- `src/routes/chat/+page.svelte` — Render `InferenceStatsPanel` after `FinalResult` when stats available

## Acceptance Criteria

- [x] InferenceStats proto message defined and TypeScript types generated
- [x] InferenceStatsPanel displays all required metrics
- [x] Panel is collapsible, collapsed by default
- [x] Context utilization shows visual progress bar
- [x] Integrates cleanly into chat page below assistant message
- [x] Dark mode support
- [x] Build, lint, typecheck pass