feat(11-03): CPV-Filter + Wert-min/max-UI in Builder, DTO, FilterPanel

TenderQueryDto gains a validated cpv[] field (single-or-repeated query
param, normalized via @Transform); buildTenderWhere adds a cpvDivisions
hasSome branch (FILTER-03, Pitfall 2 — never an exact match against raw
cpvCodes). FilterPanel gets a CPV-Division autocomplete (search-by-label,
multi-select chips, repeated ?cpv= params) plus the previously
backend-only value filter's UI: valueMin/valueMax number inputs and an
"ohne Wertangabe einschließen" toggle (default on, matches the builder's
includeNullValue default from Plan 11-01) so the 91.6% NULL-value rows
stay visible by default. Verified against the live DB: cpv=45 matches all
three raw formats ("45", "45000000", "45000000-7") via the backfilled
cpvDivisions column.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

apps/api/src/tenders/tender-query.builder.spec.ts

@@ -172,6 +172,38 @@ describe('buildTenderWhere', () => {
     );
     expect(hasGeoClause).toBe(false);
   });
+
+  it('cpv set: adds a cpvDivisions hasSome constraint (FILTER-03, Pitfall 2)', () => {
+    const where = buildTenderWhere(dto({ cpv: ['45'] }));
+
+    expect(where.AND).toEqual(
+      expect.arrayContaining([{ cpvDivisions: { hasSome: ['45'] } }]),
+    );
+  });
+
+  it('cpv with multiple divisions: hasSome carries all selected divisions', () => {
+    const where = buildTenderWhere(dto({ cpv: ['45', '71'] }));
+
+    expect(where.AND).toEqual(
+      expect.arrayContaining([{ cpvDivisions: { hasSome: ['45', '71'] } }]),
+    );
+  });
+
+  it('cpv omitted or empty is never added to AND', () => {
+    const whereUnset = buildTenderWhere(dto());
+    const whereEmpty = buildTenderWhere(dto({ cpv: [] }));
+
+    for (const where of [whereUnset, whereEmpty]) {
+      const and = (where.AND as unknown[]) ?? [];
+      const hasCpvClause = and.some(
+        (clause) =>
+          typeof clause === 'object' &&
+          clause !== null &&
+          'cpvDivisions' in (clause as Record<string, unknown>),
+      );
+      expect(hasCpvClause).toBe(false);
+    }
+  });
 });
 
 describe('buildOrderBy', () => {