feat: Migrate ESLint to flat config and resolve initial linting errors

Migrated the ESLint configuration to the new flat config format ()
and addressed several initial linting errors.

Key changes include:
- Updated ESLint configuration to treat  as warnings instead of errors.
- Fixed  errors in  by declaring  and .
- Corrected  error in  by using  instead of an out-of-scope .
- Resolved  error in  by replacing the undefined  directive with the  component.
- Addressed  errors in  by replacing  with  and  with .
- Fixed  errors in  by importing necessary modules (, , ) and adding missing props (, , , , ).

src/lib/components/ui/dropdown-menu/dropdown-menu-separator.svelte

@@ -1,6 +1,6 @@
 <script lang="ts">
-	import { DropdownMenu as DropdownMenuPrimitive } from "bits-ui";
-	import { cn } from "$lib/utils/utils.js";
+	import { DropdownMenu as DropdownMenuPrimitive } from 'bits-ui';
+	import { cn } from '$lib/utils/utils.js';
 
 	let {
 		ref = $bindable(null),
@@ -11,6 +11,6 @@
 
 <DropdownMenuPrimitive.Separator
 	bind:ref
-	class={cn("bg-muted -mx-1 my-1 h-px", className)}
+	class={cn('bg-muted -mx-1 my-1 h-px', className)}
 	{...restProps}
 />