chore: remove dead TierPicker + strike resolved gotchas

TierPicker.vue is a 5-tier preset picker from before the arbitrary-
amount contribution redesign. Zero imports across app/ and server/ —
purely dead code (99 lines).

Strike two LAUNCH_READINESS bullets that describe already-fixed
issues: the "stale tier comment" in useMemberPayment.js (no `tier`
references remain in that file), and the SeriesPassPurchase auto-
refresh gotcha (fetchPassInfo() already runs after the success path
at line 318).

app/components/TierPicker.vue

@@ -1,99 +0,0 @@
-<template>
-  <div class="tier-picker">
-    <div
-      v-for="tier in tiers"
-      :key="tier.amount"
-      class="tier-option"
-      :class="{ current: modelValue === tier.amount }"
-      @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>
-
-<script setup>
-defineProps({
-  modelValue: { type: Number, default: 0 },
-  tiers: {
-    type: Array,
-    default: () => [
-      { amount: 0, display: "$0", label: "Free" },
-      { amount: 5, display: "$5", label: "/month" },
-      { amount: 15, display: "$15", label: "/month" },
-      { amount: 30, display: "$30", label: "/month" },
-      { amount: 50, display: "$50", label: "/month" },
-    ],
-  },
-});
-
-defineEmits(["update:modelValue"]);
-</script>
-
-<style scoped>
-.tier-picker {
-  display: flex;
-  gap: 0;
-  margin-bottom: 12px;
-}
-
-.tier-option {
-  flex: 1;
-  padding: 18px 8px;
-  text-align: center;
-  border: 1px dashed var(--border);
-  background: var(--bg);
-  cursor: pointer;
-  transition: all 0.15s;
-  position: relative;
-}
-
-/* Overlap adjacent borders so dashed lines collapse into one */
-.tier-option + .tier-option {
-  margin-left: -1px;
-}
-
-.tier-option:hover {
-  background: var(--surface-hover);
-}
-
-/* Active item paints its solid border on top of any neighbor */
-.tier-option.current {
-  border-color: var(--candle);
-  border-style: solid;
-  background: var(--surface);
-  z-index: 1;
-}
-
-.tier-amount {
-  font-size: 24px;
-  font-weight: 600;
-  color: var(--text);
-  font-family: "Brygada 1918", serif;
-  display: block;
-  line-height: 1.1;
-}
-
-.tier-option.current .tier-amount {
-  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;
-  }
-  .tier-option {
-    min-width: 60px;
-  }
-}
-</style>

docs/LAUNCH_READINESS.md

@@ -144,7 +144,6 @@ See `docs/TODO.md` for:
 
 - **Admin edit does not sync Helcim `recurringAmount`.** `/admin/members/[id]` PUT writes `contributionAmount` direct to Mongo by design. Admins must PATCH Helcim manually. Worth surfacing in admin UI or docs.
 - **Cadence switch rejected on active subscriptions.** `update-contribution.post.js:184-189` refuses cadence changes mid-subscription; no UI toggle exists on `/member/account`. Adding cadence switch would require a Helcim subscription replacement flow, not a plain update.
-- **`SeriesPassPurchase.vue` doesn't auto-refresh after purchase.** (Observed 2026-04-21 during Phase 4 series-pass functional tests.) Component's local `$fetch` to `/api/series/{id}/tickets/available` fires on mount + `userEmail` watch, but isn't re-invoked after a successful purchase — the "already registered" state only appears on next navigation. Parent page calls `refreshNuxtData()` but the component doesn't participate in it. Fix: call `fetchPassInfo()` after the success toast in `handleSubmit`, or lift the fetch to `useAsyncData` so it can be refreshed from outside.
 - **S2 test fixture `id`/`slug` inconsistency.** (Local dev only.) Seeded S2 series has `id: 'test-s2-drop-in-allowed'` but `slug: 'test-s2-drop-in-allowed-series'`. Doesn't affect prod — fix the seed script if anyone re-runs fixtures and is confused why `id`-based Mongo queries return empty.
 
 ### Events-surface visual audit — deferred items (2026-04-21)
@@ -159,8 +158,6 @@ Context: Phase 4 audit against `docs/specs/events-visual-audit-findings.md` fixe
 
 ### Contribution-amount redesign — cosmetic cleanup (naming only, not behavior)
 - Rename admin members column header "Tier" → "Contribution" (`app/pages/admin/members/index.vue:265`).
-- Delete dead `app/components/TierPicker.vue`.
-- Update stale tier comment in `app/composables/useMemberPayment.js:59`.
 - Update error log message referencing "tier" in `server/api/members/update-contribution.post.js:221`.
 - Rename `handleUpdateTier` handler in `app/pages/member/account.vue`.