feat(dimensions): PR5 SIE round-trip — lossless dimension import + undo lockstep (#866)

* feat(dimensions): PR5 SIE round-trip — lossless dimension import, registry upsert, undo lockstep

SIE import previously parsed and silently DISCARDED all dimension data
(object lists at sie-parser.ts:651-654, #DIM/#OBJEKT in the ignore list at
:689). Import is now lossless — the dimensions plan PR5 milestone.

Parser: #TRANS object lists ({1 "KS01" 6 "P001"}) land on the line as an
SIE-dim-no → code map (canonical numeric keys, quoted codes, malformed
pairs warn); #DIM/#UNDERDIM/#OBJEKT parse into registry records. OIB/OUB
stay ignored (dimension reporting is P&L-only in v1).

Importer (lib/import/sie-dimensions.ts): upserts missing dimensions/
dimension_values rows — never renames existing ones (ON CONFLICT DO
NOTHING); undeclared reserved numbers synthesize their SIE-standard names
(mirroring the export's orphan synthesis); codes violating the registry
CHECK are skipped with a warning but survive verbatim on lines (documented
legacy-free-text exception). Bulk voucher insert now writes the dimensions
jsonb + cost_center/project mirrors via the sanctioned dual-write helpers
(no trigger suppression needed — the immutability trigger guards
UPDATE/DELETE, not INSERT). Import auto-enables dimensions_enabled with a
result-card notice (pre-authorized by the column comment). arcim-migration
provider syncs inherit all of it via the shared parser/importer.

Undo lockstep (migration 20260702154500): created_by_import_id provenance
on both registry tables (ON DELETE SET NULL); undo_sie_import deletes the
values/dimensions the undone import introduced when no remaining
posted/reversed line references them — user-created rows and rows other
bookkeeping references are untouched. The registry guard triggers act as
backstop. replace_sie_import deliberately skips the lockstep (re-import
re-upserts the same codes). Six pg-real tests cover the lockstep.

Round-trip pinned by test: parse → import state → export → parse preserves
declarations (#UNDERDIM parent links included), values, and per-line object
lists — including synthesis of referenced-but-undeclared values.

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

* fix(dimensions): restate function-local statement_timeout on undo_sie_import

CREATE OR REPLACE resets proconfig, so the 290s timeout from 20260629160100
was silently dropped — regressing service-client bulk deletes to the
authenticator role's 8s limit. Caught by sie-import.replace.pg.test.ts in CI.
Full pg-real suite green (483/483, TZ=UTC).

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

* fix(dimensions): surface OIB/OUB drops and dimension presence as parse-level info (#866 review)

Dropping object-balance records must never be silent — one info issue counts
the skipped #OIB/#OUB rows (object-level balances are P&L-out-of-scope in
v1), and a second announces dimension data before the user executes the
import (the preview step renders parse issues), so the auto-enable notice is
no longer purely post-hoc.

Triage notes for the remaining findings: the RPC's opening SELECT is the
company-ownership check the swarm asked for; registry writes are RLS-bound;
line-verbatim codes are the documented legacy-free-text exception; export
emits no #KSUMMA so there is nothing to recompute; SIE dims 3–5 are
"reserved for future use" with no standard names, so generic synthesis is
spec-correct; ON DELETE SET NULL is deliberate — provenance is operational
metadata for undo, not räkenskapsinformation (the guarded journal lines
are), and RESTRICT would block legitimate post-retention housekeeping.

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

---------

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

components/import/ImportResultStep.tsx

@@ -107,6 +107,33 @@ export default function ImportResultStep({ result, onNewImport, onUndo }: Import
         </Card>
       )}
 
+      {/* Dimensions detected (lossless SIE round-trip, dimensions plan PR5) */}
+      {result.success && result.dimensionsImported && (
+        <Card>
+          <CardHeader>
+            <CardTitle className="flex items-center gap-2 text-base">
+              <Info className="h-5 w-5 text-muted-foreground" />
+              Dimensioner följde med importen
+            </CardTitle>
+            <CardDescription>
+              Filen innehöll kostnadsställen/projekt: {result.dimensionsImported.taggedLines}{' '}
+              taggade rader importerades
+              {result.dimensionsImported.values > 0 && (
+                <> och {result.dimensionsImported.values} nya värden lades till i registret</>
+              )}
+              .{' '}
+              {result.dimensionsImported.toggleEnabled && (
+                <>Dimensioner aktiverades automatiskt för företaget — du hittar registret under{' '}
+                <Link href="/dimensions" className="underline underline-offset-4">
+                  Kostnadsställen &amp; projekt
+                </Link>
+                .</>
+              )}
+            </CardDescription>
+          </CardHeader>
+        </Card>
+      )}
+
       {/* Statistics */}
       {result.success && (
         <div className="grid grid-cols-2 gap-4 md:grid-cols-3">