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/ui/EntityPicker.svelte

@@ -34,8 +34,8 @@
 	let open = $state(false);
 	let query = $state('');
 	let highlightIdx = $state(0);
-	let listEl: HTMLDivElement;
-	let inputEl: HTMLInputElement;
+	let listEl = $state<HTMLDivElement>();
+	let inputEl = $state<HTMLInputElement>();
 
 	const selectedItem = $derived(items.find((i) => i.value === value));