feat(dimensions): PR10 advanced — custom dimensions, hierarchy, account rules, commit enforcement (#886)

* feat(dimensions): PR10 advanced — custom dimensions, hierarchy, account rules, commit enforcement

The final rung of the dimensions ladder
(dev_docs/dimensions_implementation_plan.md §7 row 10):

- custom dimensions: POST /api/dimensions creates registry dims (next free
  SIE number >= 20 when omitted; explicit numbers allowed — SIE import
  already mints reserved ones); register gets a 'Ny dimension' dialog with
  a quiet Avancerat disclosure for the #UNDERDIM parent; GET now carries
  parent_sie_dim_no (the column + SIE round-trip existed since PR1/PR5 —
  this exposes it)
- account_dimension_rules (migration 20260703120000): one rule per
  (account, dimension) — required / default / fixed, per-rule is_active,
  company-scoped RLS, composite FK to the registry, value-presence CHECK
- enforcement, opt-in BY CONSTRUCTION (zero rules = engine byte-identical;
  deliberately NO settings toggle — a rule that exists but is ignored is
  worse than either extreme): default/fixed apply onto line bags at draft
  creation (fixed overwrites, default fills); required asserts at
  commitEntry with a Swedish MANDATORY_DIMENSION_MISSING naming every
  account + dimension; the bulk-book route runs the same policy before its
  RPC; storno/correction paths never pass through commitEntry so history
  always reverses regardless of policy; rule fetches fail open incl.
  thrown exceptions
- chart of accounts: per-account Dimensionsregler section in
  EditAccountDialog (Krävs/Förval/Låst, value picker, pause switch),
  gated on the existing dimensions toggle, quiet when empty
- pickers: LineDimensionFields is registry-driven (one combobox per active
  dimension, cached fetch, hardcoded 1/6 fallback) — every existing mount
  lights up custom dims with zero changes
- agent briefing: per-dimension required_on_accounts/default_on_accounts
  so agents self-correct instead of bouncing off the policy error
- rules CRUD API with existence/active/company validation and qualified
  DTO ids; firm_id FK deferred until the firms table lands (per plan)

39 new tests (pure-fn rules, engine enforcement, both new API surfaces,
pg-real RLS/CHECK/cascade suite); full suite 6,791 green; migration
replayed on a fresh container.

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

* fix: renumber migration to 20260703200000 — version collision with prod

The concurrent session shipped pending_operations_add_link_document_to_voucher
as 20260703120000 today; the Supabase preview branch (cloned from prod)
rejected the duplicate version key.

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

* fix: review round — auto-pick retry on collision, fail-open warnings, query schema

- POST /api/dimensions retries once past a concurrent number claim when the
  number was auto-picked (explicit choices still 409)
- every fail-open skip of the dimension-rules policy now logs a structured
  warning (engine draft/commit paths + bulk-book) — deliberate fail-open,
  but observable
- GET /api/dimensions/rules validates its query through
  ListDimensionRulesQuerySchema instead of an inline regex

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

---------

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

lib/bookkeeping/dimension-errors.ts

@@ -97,3 +97,44 @@ export class DimensionValidationError extends Error {
 export function isDimensionValidationError(err: unknown): err is DimensionValidationError {
   return err instanceof DimensionValidationError
 }
+
+// ============================================================================
+// Mandatory dimension enforcement (dimensions PR10)
+// ============================================================================
+
+export const MANDATORY_DIMENSION_MISSING = 'MANDATORY_DIMENSION_MISSING' as const
+
+export interface MandatoryDimensionViolation {
+  account_number: string
+  /** SIE dimension number the rule requires, e.g. '6'. */
+  sie_dim_no: string
+  /** Registry display name for the dimension, e.g. 'Projekt'. */
+  dimension_name: string
+}
+
+/** Swedish user-facing sentence for a single missing-dimension violation. */
+export function formatMandatoryDimensionViolation(v: MandatoryDimensionViolation): string {
+  return `Konto ${v.account_number} kräver ${v.dimension_name} — välj ett värde innan bokföring.`
+}
+
+/**
+ * Raised at COMMIT time (commitEntry / the bulk-book pre-check) when an
+ * active 'required' rule in account_dimension_rules is unsatisfied by a
+ * line's dimensions bag. Drafts may be incomplete by design — the rule bites
+ * when the verifikat is about to become immutable. Companies without rules
+ * (every company by default) never reach this error.
+ */
+export class MandatoryDimensionMissingError extends Error {
+  readonly code = MANDATORY_DIMENSION_MISSING
+
+  constructor(public readonly violations: MandatoryDimensionViolation[]) {
+    super(violations.map(formatMandatoryDimensionViolation).join(' '))
+    this.name = 'MandatoryDimensionMissingError'
+  }
+}
+
+export function isMandatoryDimensionMissingError(
+  err: unknown,
+): err is MandatoryDimensionMissingError {
+  return err instanceof MandatoryDimensionMissingError
+}