fix(forget): populate retention groups for manual runs

internal/server/http/jobs.go

@@ -65,10 +65,32 @@ func (s *Server) handleRunNow(w stdhttp.ResponseWriter, r *stdhttp.Request) {
 func (s *Server) dispatchJob(ctx context.Context, user *store.User,
 	hostID string, kind api.JobKind, args []string,
 ) (res runNowResponse, status int, code, msg string) {
-	return s.dispatchJobWithPayload(ctx, user, hostID, kind, nil, api.CommandRunPayload{
+	payload := api.CommandRunPayload{
 		Kind: kind,
 		Args: args,
-	})
+	}
+	if kind == api.JobForget {
+		if !validForgetArgs(args) {
+			return res, stdhttp.StatusBadRequest, "invalid_args",
+				"forget accepts no arguments other than --dry-run"
+		}
+		var ok bool
+		var err error
+		payload, ok, err = s.buildForgetPayloadForHost(ctx, hostID)
+		if err != nil {
+			return res, stdhttp.StatusInternalServerError, "internal", ""
+		}
+		if !ok {
+			return res, stdhttp.StatusUnprocessableEntity, "no_retention_policy",
+				"host has no source groups with a retention policy"
+		}
+		payload.Args = args
+	}
+	return s.dispatchJobWithPayload(ctx, user, hostID, kind, nil, payload)
+}
+
+func validForgetArgs(args []string) bool {
+	return len(args) == 0 || (len(args) == 1 && args[0] == "--dry-run")
 }
 
 // dispatchJobWithPayload is dispatchJob's variant that lets callers