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>

DECISIONS.md

@@ -236,4 +236,9 @@ One line per decision: `[YYYY-MM-DD] <decision>: <why>`. Appended by agents and
 [2026-07-20] MCP gnubok_book_salary_run walks the whole review->approved->paid->booked chain in ONE staged op instead of mirroring the dashboard's four separate clicks: the human approval of the pending operation (high-risk, confirmed=true) IS the authorization act, and a four-op chain over MCP would just be approval theater. Missing bank details downgrade from overridable block to warnings (dashboard force-approve semantics): the payment-file generators hard-block on them where it matters.
 [2026-07-20] No gnubok_archive_employee tool: gnubok_update_employee already takes is_active=false (soft-archive, BFL retention) and the v1 REST surface has the DELETE verb; a dedicated tool would only bloat the tools/list budget.
 [2026-07-20] Booking core extracted to lib/salary/book-run.ts and shared by the dashboard route + book_salary_run executor; the v1 book route intentionally keeps its own strict-mode mirror (optimistic locking, period pre-check, its own envelope) rather than being folded in.
+[2026-07-20] Skattekonto sync root cause: the `ska` OAuth scope (the interactive skattekonto API's real scope, requested since the extension's first commit) was removed 2026-05-10 by a "remove unused scopes" cleanup (#431 series); every token issued after that hour gets 403 "The required scopes are not authorized" from the API. skahmst does NOT substitute (separate bulk E-transport service per its tjanstebeskrivning) and `skattekonto` is not a real SKV scope name (silently dropped from grants). Fix = re-request ska; panel scope checks now gate on ska. Kept requesting skahmst+skattekonto too: over-requesting is free, SKV grants the intersection.
+[2026-07-20] Missing-bolagsskatt warning lives in the year-end preview (previewYearEndClosing.bolagsskattMissing), not the readiness aggregator: at preflight time tax is legitimately not yet booked (it is booked later in the dispositions step), so an aggregator reminder would always fire and be noise; the preview is computed fresh right before Verkställ. Warning is advisory, never a blocker (zero tax is legit with underskottsavdrag).
+[2026-07-20] closing_entry_id made detachable via trigger escape hatch (migration 20260720140000) instead of leaving the link and relaxing app validation: the old trigger made an executed bokslut unrecoverable even pre-arsredovisning. Escape hatch demands the real storno chain (posted storno with reverses_id), not just status='reversed' (forgeable via PostgREST), and any replacement must be a posted year_end entry in the same period.
+[2026-07-20] planResultAppropriation idempotency filter narrowed to status='posted': a reversed omforing is storno-cancelled (net zero on 2099) and must not block the re-run after an administrative year-end undo. Trade-off accepted: a user who deliberately reversed the auto omforing and wants 2099 to keep carrying will get it re-posted on the next year-end/catch-up run.
+[2026-07-20] Follow-up (not done): delete_last_voucher RPC can delete the closing storno and flip the closing entry back to posted while closing_entry_id is already NULL, leaving an orphaned live closing entry; should refuse to delete stornos of year_end entries.
 [2026-07-20] Onboarding backdrop reuses marketing-site halftone webp assets copied into public/illustrations/ (not hotlinked, not regenerated): keeps app self-contained and signup->app visually continuous; decorative art uses plain <img> (physics sizes by %, next/image adds nothing for 1-35KB webp).