Use managed secret controls for Files connectors

webui/src/styles/file-manager.css

@@ -960,7 +960,7 @@
   border: 1px solid transparent;
   border-radius: 9px;
   background: transparent;
-  color: var(--ink);
+  color: var(--text-strong);
   text-align: left;
   cursor: pointer;
 }
@@ -1038,7 +1038,7 @@
   border: 0;
   border-radius: 6px;
   background: transparent;
-  color: var(--ink);
+  color: var(--text-strong);
   padding: 5px 6px;
   cursor: pointer;
 }
@@ -1137,7 +1137,7 @@
 }
 
 .managed-file-entry:disabled {
-  color: var(--ink);
+  color: var(--text-strong);
   opacity: 1;
   cursor: default;
 }
@@ -1245,7 +1245,7 @@
   border-right: 0;
   border-left: 0;
   background: transparent;
-  color: var(--ink);
+  color: var(--text-strong);
   text-align: left;
   font: inherit;
   cursor: pointer;
@@ -1272,27 +1272,6 @@
   color: var(--muted);
 }
 
-.split-field-action {
-  gap: 0;
-}
-
-.split-field-action > input,
-.split-field-action > select,
-.split-field-action > textarea {
-  border-top-right-radius: 0 !important;
-  border-bottom-right-radius: 0 !important;
-}
-
-.split-field-action > button,
-.split-field-action > .button,
-.split-field-action > .btn {
-  align-self: stretch;
-  margin-left: -1px;
-  border-top-left-radius: 0;
-  border-bottom-left-radius: 0;
-  box-shadow: none;
-}
-
 @media (max-width: 850px) {
   .managed-file-entry-head,
   .managed-file-entry {