fix(ui): disambiguate annual tier labels

"$50/yr" was ambiguous — could mean the $5 tier in annual mode or the
$50 tier in monthly mode. On /join the dropdown now shows both prices
("$5/mo → $50/yr") in annual mode. On the account page TierPicker
gains a subtitle slot; annual mode shows "$N/mo tier" beneath the
annual price so members recognize which tier they're on.

app/components/TierPicker.vue

@@ -8,6 +8,7 @@
       @click="$emit('update:modelValue', tier.amount)"
     >
       <span class="tier-amount">{{ tier.display }}</span>
+      <span v-if="tier.subtitle" class="tier-subtitle">{{ tier.subtitle }}</span>
     </div>
   </div>
 </template>
@@ -78,6 +79,15 @@ defineEmits(["update:modelValue"]);
   color: var(--candle);
 }
 
+.tier-subtitle {
+  display: block;
+  margin-top: 4px;
+  font-size: 11px;
+  color: var(--text-dim);
+  font-family: "Commit Mono", monospace;
+  letter-spacing: 0.02em;
+}
+
 @media (max-width: 768px) {
   .tier-picker {
     flex-wrap: wrap;

app/pages/join.vue

@@ -467,14 +467,19 @@ const paymentToken = ref(null);
 const circleOptions = getCircleOptions();
 
 // Minimal labels for the dropdown — reactive to cadence.
+// In annual mode, show both monthly and annual price so $50/yr (the $5 tier annual)
+// is visually distinct from $500/yr (the $50 tier annual).
 const contributionItems = computed(() => {
   return Object.values(CONTRIBUTION_TIERS).map((tier) => {
     const base = tier.amount;
     if (base === 0) return { value: tier.value, label: "$0" };
-    const amt = getTierAmount(tier, cadence.value);
-    const suffix = cadence.value === "annual" ? "/yr" : "/mo";
-    const hint = tier.value === "15" && cadence.value !== "annual" ? " (suggested)" : "";
-    return { value: tier.value, label: `$${amt}${suffix}${hint}` };
+    const monthlyLabel = `$${base}/mo`;
+    const priceLabel =
+      cadence.value === "annual"
+        ? `${monthlyLabel} → $${getTierAmount(tier, "annual")}/yr`
+        : monthlyLabel;
+    const hint = tier.value === "15" ? " (suggested)" : "";
+    return { value: tier.value, label: `${priceLabel}${hint}` };
   });
 });
 

app/pages/member/account.vue

@@ -239,10 +239,15 @@ const BASE_TIERS = [
 
 const tiers = computed(() => {
   const cadence = memberData.value?.billingCadence || 'monthly';
-  return BASE_TIERS.map((t) => ({
-    ...t,
-    display: t.amount === 0 ? '$0' : `$${getTierAmount(t, cadence)}`,
-  }));
+  return BASE_TIERS.map((t) => {
+    if (t.amount === 0) return { ...t, display: '$0' };
+    const suffix = cadence === 'annual' ? '/yr' : '/mo';
+    return {
+      ...t,
+      display: `$${getTierAmount(t, cadence)}${suffix}`,
+      subtitle: cadence === 'annual' ? `$${t.amount}/mo tier` : null,
+    };
+  });
 });
 
 const currentContributionLabel = computed(() => {