feat: Enhance invoice management with PDF optimization and date fixes

Optimize PDF export layout with compact columns and more space for partner names.
Add accounting period display to invoices matching Trial Balance format. Fix date
filtering to use local timezone instead of UTC. Update invoice ordering to
chronological sequence (DATAACT, NRACT, NUME).

**Backend changes:**
- Add accounting period query from calendar table
- Add currency (valuta) and cont filter support
- Change invoice ordering to chronological (DATAACT ASC, NRACT ASC, NUME)
- Add accounting_period field to InvoiceListResponse model

**Frontend changes:**
- Optimize PDF column widths (37% for partner names, compact numeric columns)
- Add custom column width support in exportUtils
- Fix date conversion from UTC to local timezone (prevents day shift)
- Add accounting period display in PDF exports
- Enhance E2E test coverage

**Cleanup:**
- Remove obsolete Trial Balance feature documentation

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

reports-app/backend/app/services/invoice_service.py

@@ -58,7 +58,7 @@ class InvoiceService:
                 
                 # Query cu calculele corecte pentru solduri
                 base_query = f"""
-                SELECT 
+                SELECT
                   vp.NUME,
                   vp.NRACT,
                   vp.DATAACT,
@@ -66,22 +66,23 @@ class InvoiceService:
                   vp.CONTRACT,
                   vp.COD_FISCAL,
                   vp.REG_COMERT,
-                  CASE 
+                  CASE
                     WHEN vp.CONT IN ('4111','461') THEN vp.PRECDEB + vp.DEBIT  -- Total facturat clienți
                     WHEN vp.CONT IN ('401','404','462') THEN vp.PRECCRED + vp.CREDIT  -- Total facturat furnizori
                   END as total_facturat,
-                  CASE 
+                  CASE
                     WHEN vp.CONT IN ('4111','461') THEN vp.PRECCRED + vp.CREDIT  -- Încasat clienți
                     WHEN vp.CONT IN ('401','404','462') THEN vp.PRECDEB + vp.DEBIT  -- Achitat furnizori
                   END as achitat,
-                  CASE 
-                    WHEN vp.CONT IN ('4111','461') THEN 
+                  CASE
+                    WHEN vp.CONT IN ('4111','461') THEN
                       (vp.PRECDEB + vp.DEBIT) - (vp.PRECCRED + vp.CREDIT)  -- Sold clienți
-                    WHEN vp.CONT IN ('401','404','462') THEN 
+                    WHEN vp.CONT IN ('401','404','462') THEN
                       (vp.PRECCRED + vp.CREDIT) - (vp.PRECDEB + vp.DEBIT)  -- Sold furnizori
                   END as sold,
                   vp.CONT,
-                  CASE 
+                  NVL(vp.NUME_VAL, 'RON') as valuta,
+                  CASE
                     WHEN vp.DATASCAD < SYSDATE THEN 'restant'
                     ELSE 'in_termen'
                   END as status
@@ -109,7 +110,11 @@ class InvoiceService:
                 if filter_params.partner_name:
                     base_query += " AND UPPER(vp.nume) LIKE UPPER(:partner_name)"
                     params['partner_name'] = f"%{filter_params.partner_name}%"
-                
+
+                if filter_params.cont:
+                    base_query += " AND vp.cont = :cont"
+                    params['cont'] = filter_params.cont
+
                 if filter_params.min_amount:
                     base_query += " AND total_facturat >= :min_amount"
                     params['min_amount'] = filter_params.min_amount
@@ -134,9 +139,22 @@ class InvoiceService:
                 cursor.execute(count_query, params)
                 total_count = cursor.fetchone()[0]
                 
-                # Adaugă ORDER BY și paginare
-                base_query += " ORDER BY vp.DATAACT DESC, vp.NUME, vp.NRACT"
-                
+                # Get accounting period (luna, an) from calendar
+                period_query = f"""
+                    SELECT anul, luna
+                    FROM {schema}.calendar
+                    WHERE anul*12+luna = (SELECT MAX(anul*12+luna) FROM {schema}.calendar)
+                """
+                cursor.execute(period_query)
+                period_result = cursor.fetchone()
+                accounting_period = {
+                    'an': period_result[0] if period_result else None,
+                    'luna': period_result[1] if period_result else None
+                }
+
+                # Adaugă ORDER BY și paginare - Ordonare cronologică (DATAACT, NRACT, NUME)
+                base_query += " ORDER BY vp.DATAACT ASC, vp.NRACT ASC, vp.NUME"
+
                 # Paginare Oracle
                 offset = (filter_params.page - 1) * filter_params.page_size
                 limit = offset + filter_params.page_size
@@ -147,7 +165,7 @@ class InvoiceService:
                 """
                 params['offset'] = offset
                 params['limit'] = limit
-                
+
                 cursor.execute(paginated_query, params)
                 rows = cursor.fetchall()
                 
@@ -168,8 +186,9 @@ class InvoiceService:
                     achitat = Decimal(str(row[9] or 0))
                     sold = Decimal(str(row[10] or 0))
                     cont = row[11]
-                    status = row[12]
-                    
+                    valuta = row[12] or 'RON'
+                    status = row[13]
+
                     invoice_data = {
                         'nume': nume or '',
                         'nract': nract or 0,
@@ -178,9 +197,11 @@ class InvoiceService:
                         'contract': contract,
                         'cod_fiscal': cod_fiscal,
                         'reg_comert': reg_comert,
+                        'cont': cont,
                         'totctva': total_facturat,
                         'achitat': achitat,
-                        'soldfinal': sold
+                        'soldfinal': sold,
+                        'valuta': valuta
                     }
                     
                     invoice = Invoice(**invoice_data)
@@ -194,7 +215,8 @@ class InvoiceService:
                     total_amount=total_amount,
                     page=filter_params.page,
                     page_size=filter_params.page_size,
-                    has_more=len(invoices) == filter_params.page_size
+                    has_more=len(invoices) == filter_params.page_size,
+                    accounting_period=accounting_period
                 )
     
     @staticmethod