Oracle DR: Add SHUTDOWN ABORT before NOMOUNT to clean auto-started instance

Critical fix for service auto-start behavior:

Problem (identified by user):
- When Oracle service starts, it automatically tries to start instance
- Uses configured PFILE which references control files
- After cleanup, control files don't exist
- Instance ends up in partial/error state
- STARTUP NOMOUNT may fail or behave unexpectedly

Root Cause:
- Oracle service on Windows has auto-start behavior
- Service startup takes ~30s trying to start instance
- Without valid control files, instance is partially started
- This interferes with manual STARTUP NOMOUNT

Solution:
Before STARTUP NOMOUNT, explicitly clean any existing instance:
```sql
SHUTDOWN ABORT;  -- Clean any partial instance
STARTUP NOMOUNT PFILE='...';  -- Fresh clean start
```

Implementation:
- Use WHENEVER SQLERROR CONTINUE (SHUTDOWN may error if no instance)
- Explicit SHUTDOWN ABORT before NOMOUNT
- Ensures clean instance state for RMAN restore
- Service running + clean NOMOUNT instance = ready for restore

User requirement met: Instance in NOMOUNT state (not mounted/open)

Co-authored-by: factory-droid[bot] <138933559+factory-droid[bot]@users.noreply.github.com>

oracle/standby-server-scripts/rman_restore_from_zero.ps1

@@ -88,6 +88,51 @@ $service = Get-Service -Name "OracleServiceROA" -ErrorAction SilentlyContinue
 if ($service) {
     Write-Host "[OK] Oracle service already exists, skipping creation (15s saved!)" -ForegroundColor Green
     Write-Host "    Service will be reused for this restore"
+    
+    # Ensure service is running (required for SQL*Plus connection)
+    if ($service.Status -ne "Running") {
+        Write-Host "    Service is stopped, starting it (may take 30-60 seconds)..."
+        
+        # Start service in background job to avoid blocking
+        $startJob = Start-Job -ScriptBlock {
+            Start-Service -Name "OracleServiceROA" -ErrorAction SilentlyContinue
+        }
+        
+        # Poll for service status with timeout
+        $maxWait = 60
+        $elapsed = 0
+        $pollInterval = 3
+        $serviceStarted = $false
+        
+        while ($elapsed -lt $maxWait) {
+            Start-Sleep -Seconds $pollInterval
+            $elapsed += $pollInterval
+            
+            # Refresh service status
+            $currentService = Get-Service -Name "OracleServiceROA" -ErrorAction SilentlyContinue
+            if ($currentService -and $currentService.Status -eq "Running") {
+                $serviceStarted = $true
+                Write-Host "    [OK] Service started successfully after $elapsed seconds"
+                break
+            }
+            
+            if ($elapsed % 15 -eq 0) {
+                Write-Host "    Still waiting for service to start... ($elapsed/$maxWait seconds)"
+            }
+        }
+        
+        # Cleanup background job
+        Stop-Job -Job $startJob -ErrorAction SilentlyContinue
+        Remove-Job -Job $startJob -ErrorAction SilentlyContinue
+        
+        if (-not $serviceStarted) {
+            Write-Host "    WARNING: Service did not start within $maxWait seconds" -ForegroundColor Yellow
+            Write-Host "    This may cause SQL*Plus connection issues (ORA-12560)"
+            Write-Host "    Attempting to continue anyway..."
+        }
+    } else {
+        Write-Host "    Service is already running"
+    }
 } else {
     Write-Host "    Oracle service not found, creating from PFILE..."
     
@@ -160,6 +205,19 @@ _allow_resetlogs_corruption=TRUE
 
 # Step 2.2: Startup NOMOUNT
 Write-Host "[2.2] Starting database in NOMOUNT mode..."
+
+# First, ensure any partially started instance is shut down
+# (Service auto-start may have started instance in error state without control files)
+Write-Host "    Ensuring clean state - shutting down any existing instance..."
+$cleanupSQL = @"
+WHENEVER SQLERROR CONTINUE
+SHUTDOWN ABORT;
+EXIT;
+"@
+$cleanupSQL | & sqlplus -S / as sysdba 2>&1 | Out-Null
+
+# Now start cleanly in NOMOUNT
+Write-Host "    Starting fresh instance in NOMOUNT mode..."
 $nomountSQL = @"
 STARTUP NOMOUNT PFILE='C:\Users\oracle\admin\ROA\pfile\initROA.ora';
 EXIT;