0.5.4: scrub head tapers into the playhead needle

Pentagon clip-path on the scrub handle head (flat top, straight sides
down to 55% height, triangle point at the bottom center) so the head
visually funnels into the 1px playhead needle below. box-shadow
replaced with a drop-shadow filter that respects the clip-path.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/version.ts

@@ -1,2 +1,2 @@
-export const APP_VERSION = '0.5.3'
+export const APP_VERSION = '0.5.4'
 export const APP_NAME = 'RUWIO'