feat(annotations): pass isResizable to AnnotationShape based on selection + transcribeMode

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/src/lib/components/AnnotationLayer.svelte

@@ -107,6 +107,7 @@ const containerStyle = $derived(
 			annotation={annotation}
 			isHovered={hoveredId === annotation.id}
 			isActive={annotation.id === activeAnnotationId}
+			isResizable={canDraw && annotation.id === activeAnnotationId && !annotation.polygon}
 			faded={!dimmed && !!activeAnnotationId && annotation.id !== activeAnnotationId}
 			dimmed={dimmed}
 			blockNumber={blockNumbers[annotation.id]}