Shrink a clip with the wave and drop it with a click beside (#357)

Zoomed out, the wave left room above and below it, but the bright file,
the picked clip and its handles still took the whole height. And a click
in the wave beside the picked clip kept it picked, so only the strip
could take it back to the sound.

- fileReach in waveView.ts is how far up and down the file reaches:
  full scale and its inset, never past the area. At level 1 it is the
  whole height, zoomed in too.
- The bright file, the shade outside the clip and the two handles are
  drawn within that reach.
- A click over the wave beside the picked clip picks the sound. Inside
  the clip or on a handle nothing changes, and a drag still spans the
  clip anew.

Tests:
- Unit wave-view: 11 green (1 new), a counter-check red
- e2e 34 (melektaus-atx): ALL PASSED, 91 checks (1 new)
- Gate (melektaus-atx): CHECK EXIT 0, 271 files, 4195 tests

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/editor/sound/waveView.ts

@@ -66,6 +66,14 @@ export function levelOffset(amplitude: number, level: number, half: number): num
   return amplitude * level * half;
 }
 
+/**
+ * Pixels from the middle the file and its clip reach up and down: full scale and `inset` around it,
+ * zoomed out short of the area, zoomed in never past its `room` (#357).
+ */
+export function fileReach(level: number, half: number, inset: number, room: number): number {
+  return Math.min(room, levelOffset(1, level, half) + inset);
+}
+
 /**
  * The marks of the level scale: every 6 dB down from 0, as far from the middle as they are drawn.
  * Only those within `room` of the middle and at least `minPx` from it – 6 dB halve the distance,