feat(clienti): add Oracle XE PDB recreare scripts and audit cleanup

- Complete PDB export/import workflow (16 scripts in clienti/oracle-xe-21c/import/)
- Recreare PDB script with step-by-step guide (recreare_pdb.sql)
- Universal audit cleanup script for Oracle XE 11g-21c (cleanup_audit.sql)
- Troubleshooting guide with all lessons learned (depanare-ora-12954-spatiu.md)
- Fixed: DIRECTORY grant syntax, DBMS_LOCK grant, remap_tablespace USERS:ROA,
  impdp quoted AS SYSDBA for Windows, AWR retention 8 days, datafile full path
- Updated roa-windows-setup docs with XE prevention steps and gotchas table

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

clienti/oracle-xe-21c/import/11_import_master.sql

@@ -0,0 +1,42 @@
+-- ============================================================
+-- IMPORT MASTER - Recreare PDB Oracle XE 21c
+-- Rulat ca SYS AS SYSDBA conectat la PDB-ul NOU
+-- ============================================================
+-- PREREQUISITE: PDB creat si deschis, fisierele .dmp in DMPDIR
+-- ============================================================
+
+SPOOL C:\DMPDIR\import_master.log
+
+-- ============================================================
+-- FAZA 1: Infrastructura (inainte de Data Pump)
+-- ============================================================
+PROMPT [1/13] Creating tablespaces...
+@01_tablespaces.sql
+
+PROMPT [2/13] Creating users...
+@02_useri.sql
+
+PROMPT [3/13] Creating directories...
+@03_directories.sql
+
+PROMPT [4/13] Creating SYS custom tables...
+@04_sys_tables.sql
+
+PROMPT [5/13] Creating context...
+@08_context.sql
+
+-- ============================================================
+-- FAZA 2: Data Pump (din CMD, nu din SQLPlus!)
+-- ============================================================
+PROMPT
+PROMPT ==============================================
+PROMPT  STOP! Ruleaza Data Pump din CMD:
+PROMPT ==============================================
+PROMPT  impdp \"sys/PAROLA_SYS@XEPDB1 AS SYSDBA\" directory=DMPDIR dumpfile=schemas_export.dmp logfile=schemas_import.log remap_tablespace=USERS:ROA
+PROMPT  impdp \"sys/PAROLA_SYS@XEPDB1 AS SYSDBA\" directory=DMPDIR dumpfile=sys_tables.dmp logfile=sys_tables_import.log table_exists_action=APPEND
+PROMPT ==============================================
+PROMPT  Dupa Data Pump, continua cu:
+PROMPT  @11_import_master_faza2.sql
+PROMPT ==============================================
+
+SPOOL OFF