fix(island): review findings in the controls panel

Edit mode let a right-click and the wheel through to the tile, so a
right-click opened the drawer and scroll changed volume, against the
spec. The drag area now takes both buttons and the wheel.

A scroll up on a level already above the cap, such as a mic set to 120%
elsewhere, snapped it down to the cap. The cap now only stops a step up.

Prefs logs a failed write, which printErrors off had silenced: the new
order would otherwise vanish at the next restart with no trace. Its
parsed object is renamed from data to doc, so it cannot shadow a base
property of that name.

The spec now says what was built: JSON.parse rather than a JsonAdapter,
and the helper list as it is.

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

1 files changed, 3 insertions, 0 deletions

diff --git a/desktop/island/test_controls.js b/desktop/island/test_controls.js
index f84e472..b2db873 100644
--- a/desktop/island/test_controls.js
+++ b/desktop/island/test_controls.js
@@ -82,6 +82,9 @@ assert.strictEqual(C.step(1.48, 0.05, 1.5), 1.5);
 assert.strictEqual(C.step(0.98, 0.05, 1.0), 1);
 assert.strictEqual(C.step(0.1 + 0.2, 0.05, 1), 0.35);
 assert.strictEqual(C.step(undefined, 0.05, 1), 0.05);
+// Above the cap (set elsewhere): up leaves it, down steps from where it is.
+assert.strictEqual(C.step(1.2, 0.05, 1.0), 1.2);
+assert.strictEqual(C.step(1.2, -0.05, 1.0), 1.15);
 
 // slotAt: pitch 70, 4 columns, 7 tiles.
 assert.strictEqual(C.slotAt(35, 35, 70, 4, 7), 0);