Add Windows Server Backup collector

PowerShell script for servers using Windows Server Backup, run hourly as
a SYSTEM scheduled task under Windows PowerShell 5.1. Each server is one
dashboard job.

- Backup jobs from Get-WBJob (in progress and -Previous) within the
  lookback window; restores are ignored. WSB jobs have no ID, so runs
  are keyed on start time, which also merges a Running report with the
  finished one
- Error HRESULT -> failed; detailed error or a failed item -> warning;
  messages include the error description, codes as 0x8XXXXXXX, failed
  items and the failure log path
- Next run from Get-WBSummary's NextBackupTime
- Get-WsbCollectorDiagnostics.ps1 dumps the cmdlets' real objects and
  recent Microsoft-Windows-Backup events (to check whether job times
  are local or UTC); installer adapted from the MARS one

Not yet run against a real server.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

collectors/wsb/README.md

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+# Windows Server Backup collector
+
+A PowerShell script that runs on each server using Windows Server Backup (WSB) and reports its
+backups to the dashboard. Each server appears as one job, named `<SERVER> - Windows Server Backup`
+by default.
+
+> **Not yet checked against a real server.** The cmdlets are the `WindowsServerBackup` module's own
+> (`Get-WBJob`, `Get-WBSummary`), but the properties of the objects they return, and whether job
+> times are local or UTC, aren't fully documented. Before installing on the first server, run
+> `Get-WsbCollectorDiagnostics.ps1` and the collector with `-DryRun` (see below) to confirm what it
+> reads.
+
+## Install (on the server, as an administrator)
+
+Requires the Windows Server Backup feature with its PowerShell module
+(`Install-WindowsFeature Windows-Server-Backup`). Runs under Windows PowerShell 5.1
+(`powershell.exe`), which that module targets.
+
+1. On the dashboard host, create a key for this server:
+   ```bash
+   python manage.py create-key wsb-acme-dc01
+   ```
+2. Copy this folder to the server and run:
+   ```powershell
+   .\Install-WsbCollector.ps1 -ApiUrl https://backups.example.com -Tenant "Acme Corp"
+   ```
+   Add `-JobName "Domain Controller"` to choose the name shown on the dashboard. It prompts for the
+   key, then:
+   - writes `C:\ProgramData\BackupDashboard\wsb-collector.json` (readable only by SYSTEM and Administrators)
+   - copies the script to `C:\Program Files\BackupDashboard\`
+   - registers the scheduled task **Backup Dashboard - WSB collector** (SYSTEM, every 60 minutes)
+3. Preview the payloads, then backfill 30 days so the history view is populated straight away:
+   ```powershell
+   powershell.exe -File 'C:\Program Files\BackupDashboard\Send-WsbBackupStatus.ps1' -DryRun
+   powershell.exe -File 'C:\Program Files\BackupDashboard\Send-WsbBackupStatus.ps1' -LookbackHours 720
+   ```
+
+It can be installed alongside the other collectors: it uses its own config, state, log and task.
+Re-run the installer to change settings or update the script.
+
+## What it sends
+
+| Dashboard | Windows Server Backup |
+|---|---|
+| Company | `Tenant` from the config |
+| Job | One per server, ID `wsb:<computer name>`, so changing `JobName` renames rather than duplicates it |
+| Run | One per backup job from `Get-WBJob`, identified by its start time (WSB jobs have no ID). Restores are ignored |
+| Status | Error HRESULT → **Failed**. Success, but a detailed error or a failed item (e.g. one volume) → **Warning**. Cancelled or unrecognised → **Warning**. In progress → **Running** |
+| Started / finished | Job start / end time |
+| Next scheduled | `Get-WBSummary`'s `NextBackupTime`. Empty when there's no scheduled backup |
+| Message | Error description, error codes (as `0x8XXXXXXX`), failed items, and the failure log path |
+
+Each run covers the last 48 hours (`LookbackHours`). Runs already delivered are recorded in
+`wsb-collector.state.json`.
+
+## Troubleshooting
+
+- Log: `C:\ProgramData\BackupDashboard\wsb-collector.log`. Exit codes: `0` OK, `1` some runs
+  failed to send (retried next run), `2` setup failed (config or WindowsServerBackup module).
+- Wrong status, times or messages: run `.\Get-WsbCollectorDiagnostics.ps1` (read-only). It prints
+  the real structure of what the cmdlets return, plus recent `Microsoft-Windows-Backup` events to
+  compare times against.
+
+## Testing without Windows Server Backup
+
+```powershell
+. ./tests/MockWsb.ps1                    # or: . ./tests/MockWsb.ps1 -WithRunningJob
+./Send-WsbBackupStatus.ps1 -ConfigPath ./my-test-config.json -DryRun
+```