feat(member): account/profile polish + tier upgrade flow

- Timezone: curated USelectMenu dropdown (app/config/timezones.js), preserves unknown saved values
- Profile save now uses useToast() for success/error; remove inline save banner
- Nav onboarding dot nudged down 1px for optical alignment with lowercase text
- Onboarding: skip a suggestion with POST /api/onboarding/track {skip}; member.onboarding.skipped map; does not affect graduation
- CirclePicker takes :saved-value so 'Current' badge stays until save completes
- PrivacyToggle is binary (USwitch labeled Private); member schema enum reduced to ['members','private']; zod coerces legacy 'public'
- New /member/payment-setup page: HelcimPay $0 verify + update-contribution, wired from account.vue via requiresPaymentSetup redirect
- Helcim portal: NUXT_PUBLIC_HELCIM_PORTAL_URL env + account.vue 'Manage billing in Helcim' link
- Migration script: scripts/migrate-privacy-public-to-members.js

server/api/onboarding/status.get.js

@@ -14,6 +14,8 @@ export default defineEventHandler(async (event) => {
 
   const hasClickedWiki = !!member.onboarding?.wikiClicked
 
+  const skipped = member.onboarding?.skipped || {}
+
   return {
     goals: {
       hasProfileTags,
@@ -21,6 +23,12 @@ export default defineEventHandler(async (event) => {
       hasEngagedBoard,
       hasClickedWiki,
     },
+    skipped: {
+      profileTags: !!skipped.profileTags,
+      visitEvent: !!skipped.visitEvent,
+      board: !!skipped.board,
+      wiki: !!skipped.wiki,
+    },
     completedAt: member.onboarding?.completedAt || null,
   }
 })