fix(arsredovisning): make the aktiekapital note completable via compa… (#1118)

* fix(arsredovisning): make the aktiekapital note completable via company settings

The annual report warned every AB that the aktiekapital note was missing
and pointed at Installningar -> Foretag, but the referenced columns
(aktiekapital, antal_aktier, kvotvarde) never existed and no settings UI
was ever built, so the warning was a dead end and no AB could produce a
complete note before Bolagsverket filing.

- migration 20260723103000: company_settings.aktiekapital (numeric) and
  antal_aktier (integer) with positive CHECKs; kvotvarde is intentionally
  not stored since ABL 1 kap 6 defines it as aktiekapital / antal aktier
- build-data.ts (K2 and K3 note paths): select only the two stored
  columns and derive kvotvarde with roundOre
- UpdateSettingsSchema: aktiekapital (positive), antal_aktier (positive
  integer), both nullable to allow clearing
- new ShareCapitalForm section on Installningar -> Foretag, rendered for
  aktiebolag only, with live derived kvotvarde display; wired through the
  existing CompanySettingsContent save path (empty string clears to null)
- sv/en strings; settings route tests (round-trip, clear, 400 on invalid);
  builder tests for derived kvotvarde and the empty-settings warning

Staging (metjnjrhvujscngnpzdv) already has the columns applied and the
note verified end-to-end against a rehearsal company.

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

* fix(arsredovisning): address PR review findings on the share-capital note

- enforce aktiekapital/antal_aktier as an all-or-nothing pair (DB CHECK,
  K2/K3 note guard now requires both, partial pair warns instead)
- numeric(15,2) column, .int() Zod constraint, maxFractionDigits 0 render
- guard numberOrNull against NaN; align kvotvarde preview with schema
- strengthen clearing test, add fractional and partial-pair tests

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

---------

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

messages/en.json

@@ -1322,6 +1322,12 @@
   },
   "settings_company": {
     "company_info_heading": "Company details",
+    "share_capital_heading": "Share capital",
+    "aktiekapital_label": "Share capital (SEK)",
+    "aktiekapital_help": "Registered share capital per Bolagsverket. Used in the annual report note on share capital.",
+    "antal_aktier_label": "Number of shares",
+    "antal_aktier_help": "Total number of shares per Bolagsverket.",
+    "kvotvarde_display": "Quota value per share: {value}",
     "company_name_label": "Company name",
     "company_name_help": "Shown on invoices, emails and declaration files. For a sole trader it is usually your own name (First Last).",
     "org_number_label": "Organisation number",

messages/sv.json

@@ -1322,6 +1322,12 @@
   },
   "settings_company": {
     "company_info_heading": "Företagsuppgifter",
+    "share_capital_heading": "Aktiekapital",
+    "aktiekapital_label": "Aktiekapital (kr)",
+    "aktiekapital_help": "Registrerat aktiekapital enligt Bolagsverket. Används i årsredovisningens not om aktiekapital.",
+    "antal_aktier_label": "Antal aktier",
+    "antal_aktier_help": "Totalt antal aktier enligt Bolagsverket.",
+    "kvotvarde_display": "Kvotvärde per aktie: {value}",
     "company_name_label": "Företagsnamn",
     "company_name_help": "Visas på fakturor, e-post och deklarationsfiler. För enskild firma är det vanligtvis ditt eget namn (Förnamn Efternamn).",
     "org_number_label": "Organisationsnummer",