feat(a2): port leaf PS scripts to ci_orchestrator CLI

Implements Phase A2 of plans/implementation-plan-A-B.md:

- commands/wait.py    -> wait-ready (replaces Wait-VMReady.ps1)

- commands/vm.py      -> vm remove + vm cleanup (replaces Remove-BuildVM.ps1, Cleanup-OrphanedBuildVMs.ps1); cleanup accepts injected VmBackend (Phase C ESXi hook preserved)

- commands/monitor.py -> monitor disk + monitor runner (replaces Watch-DiskSpace.ps1, Watch-RunnerHealth.ps1)

- commands/report.py  -> report job (replaces Get-CIJobSummary.ps1)

Each PS script reduced to a 3-line shim that delegates to the Python CLI and preserves \0.

Tests: 69 pytest cases across new test_commands_*.py modules; ruff clean, mypy --strict clean, coverage 74.5% (>=70 gate).

scripts/Watch-DiskSpace.ps1

@@ -1,96 +1,23 @@
 #Requires -Version 5.1
-<#
-.SYNOPSIS
-    Checks CI host drive free space and alerts via Windows Event Log (and optionally a webhook).
-
-.DESCRIPTION
-    Intended to run as a scheduled task every 15 minutes (registered by
-    Register-CIScheduledTasks.ps1). If the monitored drive is below MinFreeGB,
-    writes a Warning entry to the Windows Application Event Log under source
-    'CI-DiskAlert' (Event ID 1001) and exits with code 1 so Task Scheduler
-    marks the task as failed (visible in Task Scheduler history).
-
-    If WebhookUrl is provided, also POSTs a JSON payload to that URL
-    (compatible with Discord and Gitea webhooks — content field only).
-
-    A full drive silently causes vmrun clone to fail with cryptic errors
-    (not enough disk space for linked clone delta files). Alert early.
-
-.PARAMETER MinFreeGB
-    Alert threshold in GB. Default: 50
-
-.PARAMETER DriveLetter
-    Single letter (no colon) of the drive to monitor. Default: F
-
-.PARAMETER WebhookUrl
-    Optional Discord/Gitea webhook URL. If empty, only Event Log is written.
-
-.EXAMPLE
-    # Manual check
-    .\Watch-DiskSpace.ps1 -MinFreeGB 50
-
-    # With Discord webhook
-    .\Watch-DiskSpace.ps1 -WebhookUrl "https://discord.com/api/webhooks/..."
-#>
-[CmdletBinding()]
-param(
-    [ValidateRange(1, 2000)]
-    [int] $MinFreeGB = 50,
-
-    [ValidatePattern('^[A-Za-z]$')]
-    [string] $DriveLetter = 'F',
-
-    [string] $WebhookUrl = ''
-)
-
 Set-StrictMode -Version Latest
-$ErrorActionPreference = 'Continue'
+$ErrorActionPreference = 'Stop'
 
-$drive = Get-PSDrive -Name $DriveLetter -ErrorAction SilentlyContinue
-if (-not $drive) {
-    Write-Warning "[DiskSpace] Drive ${DriveLetter}: not found."
-    exit 2
-}
-
-$freeGB = [math]::Round($drive.Free / 1GB, 1)
-$totalGB = [math]::Round(($drive.Free + $drive.Used) / 1GB, 1)
-$pctFree = [math]::Round($freeGB / $totalGB * 100, 0)
-
-if ($freeGB -ge $MinFreeGB) {
-    Write-Host "[DiskSpace] Drive ${DriveLetter}: ${freeGB} GB free / ${totalGB} GB (${pctFree}%) — OK (threshold: ${MinFreeGB} GB)"
-    exit 0
-}
-
-# ── Alert ─────────────────────────────────────────────────────────────────────
-$msg = "CI host drive ${DriveLetter}: free space ${freeGB} GB (${pctFree}%) is below " +
-       "the ${MinFreeGB} GB threshold. vmrun linked clones may fail silently. " +
-       "Run Invoke-RetentionPolicy.ps1 or free disk space manually."
-
-Write-Warning "[DiskSpace] $msg"
-
-# Windows Event Log
-$logSource = 'CI-DiskSpaceAlert'
-try {
-    if (-not [System.Diagnostics.EventLog]::SourceExists($logSource)) {
-        New-EventLog -LogName Application -Source $logSource -ErrorAction Stop
+# Shim: delegates to the Python ci_orchestrator CLI.
+# Original PS implementation moved to git history; see plans/A2-closeout.md.
+$pyArgs = @()
+foreach ($a in $args) {
+    if ($a -is [string] -and $a.Length -gt 1 -and $a.StartsWith('-') -and -not $a.StartsWith('--')) {
+        $name  = $a.Substring(1)
+        $kebab = [Regex]::Replace($name, '(?<=[a-z0-9])([A-Z])', '-$1')
+        $kebab = [Regex]::Replace($kebab, '([A-Z]+)([A-Z][a-z])', '$1-$2')
+        $pyArgs += '--' + $kebab.ToLower()
     }
-    Write-EventLog -LogName Application -Source $logSource `
-        -EventId 1001 -EntryType Warning -Message $msg
-    Write-Host "[DiskSpace] Event Log entry written (Application/$logSource, EventId 1001)."
-} catch {
-    Write-Warning "[DiskSpace] Could not write Event Log: $_"
-}
-
-# Optional webhook (Discord / Gitea)
-if ($WebhookUrl) {
-    $body = @{ content = "[WARNING] CI Disk Alert -- $msg" } | ConvertTo-Json -Compress
-    try {
-        $null = Invoke-RestMethod -Uri $WebhookUrl -Method Post `
-            -Body $body -ContentType 'application/json' -TimeoutSec 10
-        Write-Host "[DiskSpace] Webhook notified: $WebhookUrl"
-    } catch {
-        Write-Warning "[DiskSpace] Webhook POST failed: $_"
+    else {
+        $pyArgs += $a
     }
 }
 
-exit 1   # non-zero → Task Scheduler marks run as failed (visible in history/Event Viewer)
+$venvPython = $env:CI_VENV_PYTHON
+if (-not $venvPython) { $venvPython = 'F:\CI\python\venv\Scripts\python.exe' }
+& $venvPython -m ci_orchestrator monitor disk @pyArgs
+exit $LASTEXITCODE