fix(salary): surface employee-save failures and a typed 503 for the missing encryption key (#1996) (#2009)

* fix(salary): surface employee-save failures in the dialog and type the missing encryption key (#1996)

Pressing Spara in "Ny anställd" could fail without any feedback: a thrown
fetch or a non-JSON 5xx body escaped handleSubmit before setSaving(false)
ran, leaving the button stuck on "Sparar..." and the dialog silent. Even
when the toast did fire, the Radix modal aria-hides the root-layout
Toaster, so assistive tech (and the E2E driver that found this) heard
nothing, and the requestId support needs was never shown anywhere.

- NewEmployeeDialog: fetch + parse run in a never-throwing helper, saving
  is released in finally, the body is parsed with json().catch(() => null)
  so an HTML/plain-text error page still maps through the HTTP-status map,
  and the failure is rendered inline (role="alert" in the footer) with
  "Ärende-id: <requestId>" next to the single destructive toast.
- personnummer.ts: the production "key missing" throw now carries the
  registry code PERSONNUMMER_ENCRYPTION_NOT_CONFIGURED, and the SALARY
  registry gains a 503 entry naming PERSONNUMMER_ENCRYPTION_KEY with a
  "contact support" message and a remediation hint. withRouteContext
  emits the typed envelope automatically instead of INTERNAL_ERROR 500,
  which read as transient and invited retries that can never succeed.
- Tests for the route (401, 400, 503 with requestId and no insert), the
  key guard, the registry entry, errorResponse dispatch on a coded Error,
  and getErrorMessage locale handling of the new envelope.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_015nAd8XJ2RPCmG2eKoLBdna

* fix(salary): address review findings (#1996)

- NewEmployeeDialog: fall back to the X-Request-Id response header when the
  body carries no error.requestId. The route hand-builds its 409 (duplicate
  personnummer) and generic insert-failure 500 bodies as flat strings, so the
  inline "Ärende-id" line was hidden for exactly the DB-failure class the
  issue names; withRouteContext sets the header on every response.
- Route tests pin that the 409 and 500 insert-error arms carry X-Request-Id.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_015nAd8XJ2RPCmG2eKoLBdna

---------

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

DECISIONS.md

@@ -1323,5 +1323,6 @@ One line per decision: `[YYYY-MM-DD] <decision>: <why>`. Appended by agents and
 [2026-08-28] AR-PDF minus fix uses ASCII hyphen formatting, not font embedding: registering a Unicode TTF for react-pdf would change the whole document's typography and bundle size to fix one glyph; formatPdfKronor keeps built-in Helvetica and sidesteps WinAnsi's missing U+2212.
 [2026-08-28] Same-bank warning limited to observed one-session banks (SEB only): prod shows Handelsbanken tolerates 4 concurrent sessions, and the generic warning made a user abandon a legitimate renewal. Planned sync-death visibility work was dropped: already shipped via #1271 (health probe), #1727 (stale state), #1969 (cron unstarve).
 [2026-08-28] Same-bank warning revised to three tiers after skeptic refutation: hard warn SEB, silent/calm only for verified multi-session banks (Handelsbanken, 4 distinct session_ids observed), legacy hedged warning for unknown banks (fail closed), shared-session siblings exempt (fan-out carries them).
+[2026-08-28] Employee-save failure reported inline (role=alert in the dialog footer, carrying the requestId) in addition to the single destructive toast, and a missing PERSONNUMMER_ENCRYPTION_KEY typed as 503 PERSONNUMMER_ENCRYPTION_NOT_CONFIGURED rather than INTERNAL_ERROR (#1996): the Radix modal aria-hides the root-layout Toaster while the dialog is open, so the toast is invisible to assistive tech and E2E drivers; TOAST_LIMIT is 1, so a second toast is not an option; and the missing key is a permanent configuration gap where "try again later" is wrong and "contact support" is right (same reasoning as CUSTOMER_PERSONAL_NUMBER_UNREADABLE and INVOICE_SEND_EMAIL_NOT_CONFIGURED). The shared postAction helper was not extended (it takes no body and exposes no requestId): keeping the change local to the dialog avoids widening a helper other panels rely on.
 [2026-08-28] /migrate SIE guard extended to every provider (Fortnox exemption removed) as "a completed SIE import must exist for the company", not "must be part of this run", plus a wizard hint that disables Start when SIE is unchecked and never imported; chose this over forcing the checkbox on because the route is the only seam a direct API call or a stale client cannot bypass, and "must exist" keeps entities-only re-runs after a full migration working (#2000).
 [2026-08-28] /migrate SIE guard skips company-info-only runs (all entity flags false) and the wizard derives "SIE already imported" from the preview OR this session's successful /import-sie results: company info writes no accounts, balances or subledger rows, so the BFL rationale does not apply; and the one-shot preview went stale after phase 1 succeeded and phase 2 failed, falsely blocking an entities-only retry (#2000 review).