feat(share): refactor page and enhance thumbnail extraction

- Extract 8 reusable components from monolithic share page
- Add LLM health indicator with 30s polling
- Implement stealth thumbnail extraction with 4-method cascade
- Integrate real-time thumbnail preview component
- Reduce share page from 306 to ~140 lines
- Add comprehensive outcome documentation

Components:
- UrlInputSection: URL input and extraction trigger
- ProgressIndicator: Loading state display
- ExtractedTextViewer: Collapsible text preview
- RecipeCard: Recipe display with Tandoor integration
- ErrorState: Error handling UI
- LogViewer: System logs with color coding
- LlmHealthIndicator: LLM status with polling
- ThumbnailPreview: Real-time thumbnail display

Thumbnail Methods:
1. Meta tag extraction (og:image, twitter:image)
2. Video poster attribute
3. Instagram embedded JSON data
4. Screenshot fallback

Stories Completed:
- Story 1: Component extraction and refactoring
- Story 2: LLM health status indicator
- Story 3: Enhanced stealth thumbnail extraction
- Story 4: Thumbnail preview integration

Closes: RefactorSharePageAndEnhanceThumbnails

src/routes/share/components/ProgressIndicator.svelte

@@ -0,0 +1,9 @@
+<script lang="ts">
+	let { status = 'idle' } = $props<{
+		status: string;
+	}>();
+</script>
+
+{#if status === 'extracting'}
+	<div class="animate-pulse text-blue-600">Extracting data...</div>
+{/if}