feat(fase-16): add Spinner component + unit tests

Fase 16.1 — reusable inline loading indicator. SVG circle with
stroke-dasharray + Tailwind animate-spin (respects motion-reduce).
Sizes: sm=16, md=24, lg=40. Inherits currentColor so it plays nicely
with the Fase 9 theme tokens. Wrapper has role=status + aria-live=polite
and an sr-only m.loading() label (no new Paraglide strings).

vitest.config: resolve.conditions=['browser'] + inline svelte so the
Svelte 5 mount() API resolves to index-client.js instead of the server
entry. Without it the new Spinner.test throws lifecycle_function_unavailable.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

apps/web/vitest.config.ts

@@ -16,9 +16,20 @@ export default defineConfig({
 		globals: true,
 		include: ['src/**/*.test.ts'],
 		exclude: ['tests/**', 'node_modules/**', '.svelte-kit/**'],
-		setupFiles: ['./vitest.setup.ts']
+		setupFiles: ['./vitest.setup.ts'],
+		// Force Svelte to load its browser entry (index-client.js) instead of
+		// the server entry — `mount()` only exists on the client. Without this
+		// any test that mounts a Svelte 5 component throws
+		// `lifecycle_function_unavailable`. jsdom + the `browser` condition is
+		// the canonical Svelte 5 unit-test setup.
+		server: {
+			deps: {
+				inline: [/^svelte/]
+			}
+		}
 	},
 	resolve: {
+		conditions: ['browser'],
 		alias: {
 			$lib: new URL('./src/lib', import.meta.url).pathname
 		}