fix(enable-banking): reconnect supersedes the old connection and stops duplicate imports (#1728)

* fix(enable-banking): supersede the old connection on bank reconnect and stop renewal duplicates

A renewal performed via the bank list ("Anslut ny bank") created a second
bank_connections row and left the old one parked in 'expired' forever: an
eternal "Åtgärd krävs" card, a red status chip, transactions stranded on the
dead row (so the picker's gap-fill probe read the renewal as a first
connect), and re-imported history for no-IBAN accounts whose provider uids
change on re-authorization.

- New migration: additive superseded_by uuid (FK, ON DELETE SET NULL) +
  superseded_at + partial index on bank_connections. Status 'revoked' is
  reused for superseded rows (no CHECK change); superseded_by disambiguates
  a supersede from a user disconnect. File only: not applied anywhere yet.
- New lib/supersede.ts: after the OAuth callback finalizes, park same-bank
  siblings matched by IBAN overlap (an ACTIVE sibling without overlap is
  never touched; no-IBAN fallback only for dead siblings when neither side
  has IBANs), revoke their EB session only when countLiveSiblings says
  nobody shares it, re-point their transactions in id batches, demote
  leftover cash_accounts claims (the mirror then promotes them by IBAN),
  carry last_synced_at + initial_sync_* onto the survivor, and emit the new
  bank_connection.superseded audit event.
- /connect fresh path: 409 { code: 'EXISTING_CONNECTION',
  existing_connection_id } when a non-revoked same-bank row exists, unless
  the body carries force_new: true (escape hatch for a second login at the
  same bank). Runs after the zombie sweep; reconnect-in-place unaffected.
- Dedup scope stability: StoredAccount.dedup_scope pins the external_id
  account scope at first ingest (normalized IBAN, else the uid of that
  moment), is carried across in-place reconnects and supersedes by IBAN
  match, and sync.ts uses dedup_scope ?? IBAN ?? uid (stamping legacy rows
  lazily). The external_id FORMAT is untouched.
- AccountPickerDialog gap-fill probe also includes superseded connection
  ids so the renewal default never races the transaction re-point.
- Sync toast (BankSyncNowButton) now also reports skipped duplicates
  (sv+en strings) so a correctly deduped renewal does not look broken.

Tests: supersede unit tests, /connect 409 + force_new, callback supersede
wiring + dedup-scope carry, sync external_id stability across uid changes.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

* fix(enable-banking): scope the connect 409 to dead siblings and harden supersede ordering

- POST /connect only 409s when the same-bank sibling is expired/error/
  pending_selection: an active row (a second legitimate login at the same
  bank) never blocks a fresh connect; force_new bypass kept. The 409 text
  now names the bank and points at Fornya samtycke.
- supersede parks the sibling row BEFORE revoking its EB session, and skips
  the revoke entirely (logged) when the park update fails, so a failed park
  can no longer leave a live-looking row with a dead session.
- callback keeps a survivor account's explicit dedup_scope instead of
  letting a carried sibling scope clobber it; carried scopes only apply
  when the survivor's scope was derived (IBAN/uid fallback).
- sync-now toast joins its two sentences with '. ' so the imported and
  skipped-duplicates messages no longer run together.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

---------

Co-authored-by: Jakob Wennberg <311770904+jakobwennberg-oss@users.noreply.github.com>
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>

extensions/general/enable-banking/components/AccountPickerDialog.tsx

@@ -263,11 +263,29 @@ export function AccountPickerDialog({
     if (!open || !isInitialSelection || !company?.id || accounts.length === 0) return
     let cancelled = false
     ;(async () => {
+      // Include rows this connection superseded: a renewal that arrived via a
+      // fresh connect owns no transactions until the callback's supersede has
+      // re-pointed them, and the gap-fill default must not depend on winning
+      // that race. A failed lookup (e.g. column not deployed yet) falls back
+      // to probing this connection alone.
+      let probeConnectionIds: string[] = [connectionId]
+      const { data: supersededRows, error: supersededError } = await supabase
+        .from('bank_connections')
+        .select('id')
+        .eq('company_id', company.id)
+        .eq('superseded_by', connectionId)
+      if (cancelled) return
+      if (!supersededError && supersededRows) {
+        probeConnectionIds = [
+          connectionId,
+          ...(supersededRows as Array<{ id: string }>).map((r) => r.id),
+        ]
+      }
       const { data, error } = await supabase
         .from('transactions')
         .select('date')
         .eq('company_id', company.id)
-        .eq('bank_connection_id', connectionId)
+        .in('bank_connection_id', probeConnectionIds)
         .order('date', { ascending: false })
         .limit(1)
         .maybeSingle()