feat(year-end): administrative undo of executed year-end closing + skatteverket scope fixes (#1081)

* fix(skatteverket): request the ska scope for skattekonto v2

The skattekonto v2 API rejects skahmst-only tokens with 403 "The required
scopes are not authorized" (observed in prod 2026-07-20; no company has
synced since 2026-05-10). The requested `skattekonto` scope is silently
dropped from every grant, while `ska` appears in one real May grant, so
request it too: SKV grants the intersection, so this is harmless if wrong.

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

* fix(skatteverket): correct the skattekonto scope model around ska

Root cause of the May 10 skattekonto outage, confirmed via git history and
prod token data: the `ska` scope (the interactive skattekonto API's actual
scope, requested since the extension's first commit in March) was removed
by the "remove unused scopes" cleanup in the #431 series. Every token
issued after that hour lacks it and the API answers 403 "The required
scopes are not authorized"; no company has synced since. The May 15 repair
re-added skahmst, which per its tjanstebeskrivning is a different bulk
E-transport service and does not substitute; `skattekonto` is not a real
SKV scope name and is silently dropped from grants.

Follow-up to the ska re-request (cd8f7a30):
- document the confirmed scope model in oauth.ts so ska is never
  "cleaned up" again
- panel missing-scope warning and reconnect-button now gate on ska,
  not skahmst/skattekonto
- scope badge labels: ska takes the saldo & transaktioner label,
  skahmst relabeled as the E-transport file service
- consent-page note covers both terse scope names and says ska is
  required

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

* fix(year-end): warn on untaxed profit at verkstall, Swedish readiness messages, always-visible period selector

An aktiebolag could execute year-end with a profit and zero bolagsskatt
booked without any warning (support case: closing moved 592k to 2099
untaxed). The preview now computes bolagsskattMissing (AB + profit + no
89xx account among closed accounts, 8999 excluded) and both the preview
and execute steps render an advisory, bypassable warning.

validateYearEndReadiness messages are now Swedish (the bokslut wizard is
a stays-Swedish surface); the MCP year_end_readiness classifier matches
both the new Swedish strings and the legacy English ones.

The wizard period selector now always renders, keeps a selected-but-
ineligible period selectable, and resets a stale ?period= id from
another company instead of leaving the user stuck on the wrong year.

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

* feat(year-end): administrative undo of an executed year-end closing

Storno-only reset used when a bokslut was executed prematurely (e.g.
without bolagsskatt) and no arsredovisning exists yet: reverses the next
period's result_appropriation and opening_balance entries, reopens the
period, reverses the closing entry, and detaches closing_entry_id.
Resumable if interrupted midway; attribution per BFL 5 kap 6.

Migration 20260720140000 adds the trigger escape hatch: closing_entry_id
may only change once set when the old closing entry is reversed with a
posted storno chain (status flag alone is forgeable via PostgREST), and
a non-NULL replacement must be a posted year_end entry in the same
period. Covered by a pg-real test.

planResultAppropriation idempotency is now posted-only: a reversed
omforing no longer blocks the re-run from posting a fresh 2099 -> 2098
reclassification (it previously returned null silently, leaving the new
year's equity polluted).

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

* fix(review): address CodeRabbit, PR-Agent and compliance findings

- undo script: company_id filters on verify queries, period-scope the
  arsredovisning precondition checks, validate service-key format,
  escalate audit_log insert failure to a hard error (BFNAR 2013:2)
- detach migration: company-scope the storno chain EXISTS, replace the
  em dash in the new error message

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

* fix(review): address round-2 compliance swarm and Swedish review findings

- undo script: require --confirm-url with --commit so an env swap fails
  loud; retry the audit_log insert 3x and direct the operator to insert
  the behandlingshistorik row manually on final failure (BFNAR 2013:2)
- year-end preview: document why resultAccountSummary is a complete 89xx
  scan; warning text now also names periodiseringsfond and
  overavskrivningar as legitimate zero-tax reasons

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

---------

Co-authored-by: Claude Fable 5 <noreply@anthropic.com>

app/(dashboard)/bookkeeping/year-end/page.tsx

@@ -86,18 +86,37 @@ export default function YearEndPage() {
           return
         }
         const { data } = (await res.json()) as { data: FiscalPeriod[] }
+        const all = data ?? []
         const today = new Date().toISOString().split('T')[0]
-        const eligible = (data ?? []).filter(
+        const eligible = all.filter(
           (p) => !p.is_closed && !p.closing_entry_id && p.period_end <= today,
         )
         // Oldest first: accountants close in order.
         eligible.sort((a, b) => a.period_start.localeCompare(b.period_start))
         if (cancelled) return
-        setPeriods(eligible)
-        setHasAnyPeriods((data ?? []).length > 0)
-        if (!selectedPeriodId && eligible.length > 0) {
+        setHasAnyPeriods(all.length > 0)
+
+        // The URL ?period= param may point anywhere: at an ineligible period
+        // (e.g. a year that has not ended) or, after a company switch, at a
+        // period that does not exist in this company at all. An unknown id is
+        // reset to the first eligible period; a known-but-ineligible one is
+        // kept selectable in the dropdown so the user can navigate away from
+        // it instead of being stuck (the readiness step explains why it
+        // cannot be closed).
+        let options = eligible
+        if (selectedPeriodId) {
+          const known = all.find((p) => p.id === selectedPeriodId)
+          if (!known) {
+            setSelectedPeriodId(eligible.length > 0 ? eligible[0].id : null)
+          } else if (!eligible.some((p) => p.id === selectedPeriodId)) {
+            options = [...eligible, known].sort((a, b) =>
+              a.period_start.localeCompare(b.period_start),
+            )
+          }
+        } else if (eligible.length > 0) {
           setSelectedPeriodId(eligible[0].id)
         }
+        setPeriods(options)
       } catch {
         if (!cancelled) setPeriodsError('Kunde inte hämta perioder')
       }
@@ -256,7 +275,7 @@ export default function YearEndPage() {
         )
       )}
 
-      {showWizard && periods && periods.length > 1 && step !== 'result' && (
+      {showWizard && periods && periods.length > 0 && step !== 'result' && (
         <Card>
           <CardContent className="p-4 flex items-center gap-4">
             <label className="text-sm font-medium shrink-0">Period</label>
@@ -349,6 +368,7 @@ export default function YearEndPage() {
           periodName={report.period.name}
           isRunning={executing}
           error={executeError}
+          bolagsskattMissing={preview?.bolagsskattMissing ?? false}
           onBack={() => setStep('preview')}
           onExecute={executeYearEnd}
         />