feat: upgrade empty states with welcome message and column placeholders

src/components/boards/BoardList.tsx

@@ -24,14 +24,20 @@ export function BoardList() {
   if (boards.length === 0) {
     return (
       <>
-        <div className="flex h-full flex-col items-center justify-center gap-4">
-          <p className="font-mono text-sm text-pylon-text-secondary">
-            Create your first board
-          </p>
-          <div className="flex items-center gap-2">
-            <Button onClick={() => setDialogOpen(true)}>
+        <div className="flex h-full flex-col items-center justify-center gap-6">
+          <div className="text-center">
+            <h2 className="font-heading text-2xl text-pylon-text">
+              Welcome to OpenPylon
+            </h2>
+            <p className="mt-2 max-w-sm text-sm text-pylon-text-secondary">
+              A local-first Kanban board that keeps your data on your machine.
+              Create your first board to get started.
+            </p>
+          </div>
+          <div className="flex items-center gap-3">
+            <Button size="lg" onClick={() => setDialogOpen(true)}>
               <Plus className="size-4" />
-              New Board
+              Create Board
             </Button>
             <ImportExportButtons />
           </div>