fix(auth): surface rate-limit error on login and remove dropped background patterns

Show a clear too-many-attempts message on the login page when the server
throttles the request. Remove the nova and golden-ratio background options,
whose CSS definitions were already deleted.

client/src/assets/main.css

@@ -153,32 +153,6 @@
   filter: contrast(150%) brightness(110%);
 }
 
-.pattern-nova::before {
-  content: '';
-  position: fixed;
-  inset: 0;
-  z-index: -1;
-  pointer-events: none;
-  background-image:
-    radial-gradient(at 50% 50%, oklch(0.7 0.15 var(--tint-h) / 0.12) 0%, transparent 60%),
-    linear-gradient(to bottom, oklch(0.7 0.15 calc(var(--tint-h) + 150) / 0.08) 0%, transparent 40%),
-    linear-gradient(to top, oklch(0.7 0.15 calc(var(--tint-h) + 210) / 0.08) 0%, transparent 40%);
-  filter: contrast(150%) brightness(110%);
-}
-
-.pattern-golden-ratio::before {
-  content: '';
-  position: fixed;
-  inset: 0;
-  z-index: -1;
-  pointer-events: none;
-  background-image:
-    radial-gradient(at 38.2% 38.2%, oklch(0.7 0.15 var(--tint-h) / 0.1) 0%, transparent 55%),
-    radial-gradient(at 61.8% 61.8%, oklch(0.7 0.15 calc(var(--tint-h) + 137.5) / 0.1) 0%, transparent 55%),
-    radial-gradient(at 80% 20%, oklch(0.7 0.15 calc(var(--tint-h) + 275) / 0.08) 0%, transparent 50%);
-  filter: contrast(150%) brightness(110%);
-}
-
 .pattern-millimeter::before {
   content: '';
   position: fixed;

client/src/features/auth/LoginPage.vue

@@ -59,6 +59,20 @@ const loading = ref(false)
 const oidcProviders = ref<OidcProviderPublic[]>([])
 const oidcLoadingSlug = ref<string | null>(null)
 
+function resolveLoginError(err: unknown): string {
+  if (!(err instanceof Error)) return 'Invalid username or password'
+
+  const normalizedMessage = err.message.trim().toLowerCase()
+  if (normalizedMessage.includes('too many requests') || normalizedMessage.includes('throttler')) {
+    return 'Too many login attempts. Please wait a minute and try again.'
+  }
+  if (normalizedMessage.includes('invalid credentials')) {
+    return 'Invalid username or password'
+  }
+
+  return err.message || 'Invalid username or password'
+}
+
 onMounted(async () => {
   oidcProviders.value = await getPublicProviders()
 })
@@ -68,8 +82,8 @@ async function handleSubmit() {
   loading.value = true
   try {
     await login(username.value, password.value)
-  } catch {
-    error.value = 'Invalid username or password'
+  } catch (err) {
+    error.value = resolveLoginError(err)
   } finally {
     loading.value = false
   }

client/src/features/settings/AppearanceSettings.vue

@@ -41,7 +41,7 @@ const BACKGROUND_GROUPS: { label: string; ids: string[] }[] = [
   { label: 'Fundamental', ids: ['none', 'dots', 'cross', 'terminal', 'millimeter'] },
   { label: 'Structural', ids: ['blueprint', 'brushed', 'scanlines', 'vinyl', 'carbon', 'perforated'] },
   { label: 'Ambient', ids: ['aurora', 'horizon', 'glow', 'mesh', 'elevation'] },
-  { label: 'Refractive', ids: ['prism', 'spectrum', 'spectrum-x', 'spectrum-plus', 'eclipse', 'nova', 'golden-ratio'] },
+  { label: 'Refractive', ids: ['prism', 'spectrum', 'spectrum-x', 'spectrum-plus', 'eclipse'] },
 ]
 
 const accentLabel = computed(() => [...ACCENT_VIVID, ...ACCENT_PASTEL].find((opt) => opt.id === themeStore.accent)?.label ?? themeStore.accent)

client/src/stores/theme.ts

@@ -61,8 +61,6 @@ export type Background =
   | 'spectrum-x'
   | 'spectrum-plus'
   | 'eclipse'
-  | 'nova'
-  | 'golden-ratio'
 
 export const ACCENT_VIVID: { id: Accent; label: string; color: string }[] = [
   { id: 'white', label: 'White', color: '#fafafa' },
@@ -140,8 +138,6 @@ export const BACKGROUND_OPTIONS: { id: Background; label: string; cssClass: stri
   { id: 'spectrum-x', label: 'Spectrum X', cssClass: 'pattern-spectrum-x' },
   { id: 'spectrum-plus', label: 'Spectrum Plus', cssClass: 'pattern-spectrum-plus' },
   { id: 'eclipse', label: 'Eclipse', cssClass: 'pattern-eclipse' },
-  { id: 'nova', label: 'Nova', cssClass: 'pattern-nova' },
-  { id: 'golden-ratio', label: 'Golden Ratio', cssClass: 'pattern-golden-ratio' },
 ]
 
 const ACCENT_IDS = ACCENT_OPTIONS.map((a) => a.id)