Type a repeat delay as whole milliseconds

The two On key down fields read in milliseconds now, and say so in their
labels. A number field shows three decimals unless a property asks for
fewer, so both params set decimals: 0 – the field reads 300, not 300.000,
and rounds to whole milliseconds while typing or scrubbing. The clock
behind it still counts seconds; the conversion sits at the one place that
reads the properties.

src/core/graph/nodes/events/OnKeyDown.ts

@@ -11,8 +11,26 @@ export const OnKeyDown: NodeDef = {
   outputs: [exec()],
   params: [
     keyParam,
-    { key: 'repeatAfter', label: 'Repeat after (ms)', kind: 'number', default: 0, min: 0, step: 50 },
-    { key: 'repeatInterval', label: 'Repeat interval (ms)', kind: 'number', default: 0, min: 0, step: 10 },
+    // `decimals: 0`: a millisecond is the finest step the repeat clock reads, so a fractional
+    // field would only ever show a ".000" nothing can use.
+    {
+      key: 'repeatAfter',
+      label: 'Repeat after (ms)',
+      kind: 'number',
+      default: 0,
+      min: 0,
+      step: 50,
+      decimals: 0,
+    },
+    {
+      key: 'repeatInterval',
+      label: 'Repeat interval (ms)',
+      kind: 'number',
+      default: 0,
+      min: 0,
+      step: 10,
+      decimals: 0,
+    },
   ],
   // Both rows go together: with no delay there is no repeat, so the interval is not in play either.
   hiddenParams: (params) => (asNumber(params.repeatAfter ?? 0) > 0 ? [] : ['repeatAfter', 'repeatInterval']),