webui: show all RAID drives per controller and add drive-prepare action

RAID Controller Management previously hid any LSI drive that wasn't
already Frgn/UGood/JBOD, and scoped VROC "free drives" from all system
disks instead of the ones actually wired to the VROC controller's
ports - drives attached directly to the CPU or another HBA could leak
in. Now every drive is listed per its own controller, and LSI drives
not already ready for array creation get a "Prepare" button that
forces them to Unconfigured Good via storcli.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

audit/internal/webui/server.go

@@ -323,6 +323,7 @@ func NewHandler(opts HandlerOptions) http.Handler {
 	mux.HandleFunc("GET /api/tools/raid/status", h.handleAPIRAIDStatus)
 	mux.HandleFunc("POST /api/tools/raid/foreign", h.handleAPIRAIDForeignAction)
 	mux.HandleFunc("POST /api/tools/raid/create-mirror", h.handleAPIRAIDCreateMirror)
+	mux.HandleFunc("POST /api/tools/raid/prepare-drive", h.handleAPIRAIDPrepareDrive)
 
 	// GPU presence / tools
 	mux.HandleFunc("GET /api/gpu/presence", h.handleAPIGPUPresence)