fix: resolve all linter errors and a11y warnings

- Fix TS errors: editMode property order, implicit any, string|undefined
- Add $state() to bind:this element refs (IconGrid, EntityPicker, etc.)
- Fix a11y: labels, aria-labels, roles, tabindex on dialogs
- Remove unused imports (tick, svelte-i18n)
- Make AutocompleteInput/TagsInput accept optional string values

src/lib/components/board/BoardShareDialog.svelte

@@ -148,10 +148,11 @@
 <svelte:window onkeydown={handleKeydown} />
 
 <!-- Backdrop -->
-<!-- svelte-ignore a11y_click_events_have_key_events a11y_no_static_element_interactions -->
+<!-- svelte-ignore a11y_click_events_have_key_events -->
 <div
 	class="fixed inset-0 z-50 flex items-center justify-center bg-black/50"
 	onclick={handleBackdropClick}
+	role="presentation"
 >
 	<div class="mx-4 w-full max-w-lg rounded-xl border border-border bg-card p-6 shadow-xl" role="dialog" aria-modal="true">
 		<!-- Header -->