fix: Polish diacritics + DGET CellError explicit guard

- plPL: DCOUNTA 'BD.ILE.REKORDOW.A' -> 'BD.ILE.REKORDÓW.A' (missing Ó,
  matches DCOUNT pattern; Cursor Bugbot finding).
- plPL: DAVERAGE 'BD.SREDNIA' -> 'BD.ŚREDNIA' (missing Ś, per Microsoft
  Polish documentation; pre-emptive fix for the same class of issue).
- DGET: explicit CellError check on the matched cell makes the error-
  propagation path consistent with the other D-functions (previously
  worked by accident via fall-through).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: marcin-kordas-hoc

src/i18n/languages/plPL.ts

@@ -75,9 +75,9 @@ const dictionary: RawTranslationPackage = {
     DAYS360: 'DNI.360',
     DAYS: 'DNI',
     DB: 'DB',
-    DAVERAGE: 'BD.SREDNIA',
+    DAVERAGE: 'BD.ŚREDNIA',
     DCOUNT: 'BD.ILE.REKORDÓW',
-    DCOUNTA: 'BD.ILE.REKORDOW.A',
+    DCOUNTA: 'BD.ILE.REKORDÓW.A',
     DGET: 'BD.POLE',
     DMAX: 'BD.MAX',
     DMIN: 'BD.MIN',

src/interpreter/plugin/DatabasePlugin.ts

@@ -237,11 +237,15 @@ export class DatabasePlugin extends FunctionPlugin implements FunctionPluginType
 
       for (let rowIdx = 1; rowIdx < dbData.length; rowIdx++) {
         if (this.rowMatchesCriteria(dbData[rowIdx], criteriaRows)) {
+          const cellValue = dbData[rowIdx][fieldIndex]
+          if (cellValue instanceof CellError) {
+            return cellValue
+          }
           matchCount++
           if (matchCount > 1) {
             return new CellError(ErrorType.NUM, ErrorMessage.ValueLarge)
           }
-          matchedValue = dbData[rowIdx][fieldIndex]
+          matchedValue = cellValue
         }
       }