refactor(combobox): SelectedTags as band above the Control (Chakra pattern)

Switched the multi-mode chips from MUI-style "inline inside the input"
to the Chakra v3 multi-select pattern — chips render as a separated
band ABOVE the Control. Two wins:

- The dropdown popover (opens downward) never covers the selected
  chips, which sit comfortably above the input.
- The Control stays a normal-height single-line input. No layout
  shifts, no absolute-positioned affordances, no `display: contents`
  gymnastics, no input flex tuning.

Reverts the inside-the-Control CSS gymnastics from `30e9517a` /
`64bbe9b1` / `87e3d68f` (flex-wrap, padding-right reservation,
absolute clear+trigger, input flex basis). `<Combobox.SelectedTags>`
now renders as a plain `flex-wrap` row with chip gap and a margin-
block-end separating it from the Control. Demo composes
`<Combobox.SelectedTags />` BEFORE `<Combobox.Control>` when
`mode === 'multiple'`.

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

src/uix/eidos/components/combobox/combobox.css

@@ -88,7 +88,6 @@
 	box-sizing: border-box;
 	display: flex;
 	align-items: center;
-	flex-wrap: wrap;
 	gap: var(--_combobox-control-gap);
 	inline-size: 100%;
 	min-inline-size: 0;
@@ -165,11 +164,9 @@
 
 [data-combobox-input] {
 	box-sizing: border-box;
-	/* Basis `4rem` lets the input share a wrapped row with chips +
-	 * clear/trigger affordances while still growing to fill any remaining
-	 * space. Pure `inline-size: 100%` forces a new line under flex-wrap. */
-	flex: 1 1 4rem;
-	min-inline-size: 4rem;
+	flex: 1 1 auto;
+	inline-size: 100%;
+	min-inline-size: 0;
 	border: 0;
 	background: transparent;
 	color: inherit;
@@ -493,59 +490,25 @@
 	}
 }
 
-/* SelectedTags — logical group for the chip strip. Uses
- * `display: contents` so each chip becomes a direct flex child of
- * `<Combobox.Control>` instead of being nested in its own row. This
- * lets the input flow on the same wrapped row as the last chip
- * (Material UI Autocomplete behaviour) rather than always dropping
- * to a fresh row below the whole tag block. */
+/* SelectedTags — chip strip rendered ABOVE the Control so the
+ * dropdown popover (which opens downward) never covers the selected
+ * values. Chakra v3 multi-select pattern: clean separated band, the
+ * Control stays plain `<input>` height with no layout shift. */
 [data-combobox-selected-tags] {
-	display: contents;
+	display: flex;
+	flex-wrap: wrap;
+	align-items: center;
+	gap: var(--space-1-5);
+	margin-block-end: var(--space-2);
+	min-inline-size: 0;
 }
 
-/* Empty state — element stays in DOM (so `:has(...:not([data-empty]))`
- * still works for layout siblings) but no children render. */
+/* Hide entirely when no chips so the Control isn't pushed down by an
+ * empty band. */
 [data-combobox-selected-tags][data-empty] {
 	display: none;
 }
 
-/* Material UI Autocomplete pattern — when chips are present, pin the
- * right-side affordances absolutely so chips + input wrap freely
- * without ever pushing the clear/trigger to a new row.
- *
- * `--_combobox-affordances-w` reserves the right-padding the
- * absolutely-positioned ClearButton + Trigger consume (each is ~26px
- * wide with size=md, scaled below for xs/sm/lg/xl). */
-[data-combobox-control]:has([data-combobox-selected-tags]:not([data-empty])) {
-	--_combobox-affordances-w: calc(var(--_combobox-control-height) * 2);
-	position: relative;
-	padding-block: var(--space-1);
-	padding-inline-end: calc(var(--_combobox-control-px) + var(--_combobox-affordances-w));
-}
-
-[data-combobox-control]:has([data-combobox-selected-tags]:not([data-empty]))
-	[data-combobox-clear-button],
-[data-combobox-control]:has([data-combobox-selected-tags]:not([data-empty]))
-	[data-combobox-trigger] {
-	position: absolute;
-	/* Pin to the FIRST row of the wrapped control so the affordances stay
-	 * aligned with the input + chip row even when many chips wrap into
-	 * extra rows below. `padding-block` (var(--space-1)) is the control's
-	 * top offset; matching that here keeps the buttons flush with the
-	 * first chip / input row. */
-	inset-block-start: var(--space-1);
-}
-
-[data-combobox-control]:has([data-combobox-selected-tags]:not([data-empty]))
-	[data-combobox-clear-button] {
-	inset-inline-end: calc(var(--_combobox-control-px) + var(--_combobox-control-height));
-}
-
-[data-combobox-control]:has([data-combobox-selected-tags]:not([data-empty]))
-	[data-combobox-trigger] {
-	inset-inline-end: var(--_combobox-control-px);
-}
-
 [data-combobox-selected-tag] {
 	display: inline-flex;
 	align-items: center;

web/routes/uix/components/combobox/+page.svelte

@@ -265,10 +265,10 @@
 				{color}
 				name="framework"
 			>
-				<Combobox.Control>
 				{#if mode === 'multiple'}
 					<Combobox.SelectedTags />
 				{/if}
+				<Combobox.Control>
 					<Combobox.Input
 						placeholder="Search framework..."
 						data-perm-step={!disabled ? '0' : undefined}