refactor: convert to bun workspaces monorepo

- Move web app into apps/web/
- Create packages/shared/ with shared types
- Create plugins/decky-vault/ scaffold
- Root package.json manages workspaces only

apps/web/app/globals.css

@@ -0,0 +1,57 @@
+@import "tailwindcss";
+@plugin "@tailwindcss/typography";
+
+@theme inline {
+    /* Colors */
+    --color-background: #100b14;
+    --color-foreground: #180161;
+    --color-primary: #eb3779;
+    --color-secondary: #571b8b;
+    --color-accent: #fb793c;
+    --color-text: #ebe4f1;
+    --color-border: color-mix(in srgb, var(--color-text) 20%, transparent);
+    --color-border-active: color-mix(
+        in srgb,
+        var(--color-text) 60%,
+        transparent
+    );
+
+    /* Defaults */
+    --default-transition-duration: 0.3s;
+
+    /* Fonts */
+    --font-sans: var(--font-lexend);
+}
+
+/* Touch targets — WCAG 2.1 AA: minimum 44×44px */
+.touch-target {
+    min-height: 44px;
+    min-width: 44px;
+}
+
+/* Gamepad focus ring — visible only when gamepad navigation is active */
+.gamepad-focus :focus,
+.gamepad-focus:focus-visible {
+    outline: 2px solid var(--color-primary);
+    outline-offset: 2px;
+    border-radius: 4px;
+}
+
+/* Thin scrollbar for horizontal scroll sections */
+.scrollbar-thin {
+    scrollbar-width: thin;
+    scrollbar-color: color-mix(in srgb, var(--color-text) 15%, transparent) transparent;
+}
+
+.scrollbar-thin::-webkit-scrollbar {
+    height: 4px;
+}
+
+.scrollbar-thin::-webkit-scrollbar-track {
+    background: transparent;
+}
+
+.scrollbar-thin::-webkit-scrollbar-thumb {
+    background: color-mix(in srgb, var(--color-text) 15%, transparent);
+    border-radius: 2px;
+}