feat(extension): field-history pane visual polish — section headers + glyph buttons

extension/src/vault/vault.css

@@ -1111,66 +1111,28 @@ textarea {
   margin-bottom: 12px;
 }
 
-.history-field-label {
-  font-size: 11px;
-  color: #8b949e;
-  text-transform: uppercase;
-  margin: 12px 0 6px;
-}
-
 .history-entry {
-  display: flex;
+  display: grid;
+  grid-template-columns: 1fr auto;
+  gap: 6px;
   align-items: center;
-  gap: 8px;
-  padding: 10px;
-  border-radius: 4px;
-  background: #161b22;
-  margin-bottom: 6px;
-  cursor: pointer;
+  padding: 8px 0;
+  border-bottom: 1px solid var(--border-subtle);
 }
-
-.history-entry:hover {
-  background: #1c2128;
-}
-
 .history-entry__value {
-  flex: 1;
-  font-family: monospace;
-  font-size: 13px;
+  font-family: ui-monospace, monospace;
+  word-break: break-all;
 }
-
-.history-entry__value.masked {
-  color: #8b949e;
-}
-
-.history-entry__value.revealed {
-  color: #c9d1d9;
-}
-
+.history-entry__value.masked { letter-spacing: 1px; }
 .history-entry__meta {
-  display: flex;
-  flex-direction: column;
-  align-items: flex-end;
-  gap: 2px;
+  grid-column: 1 / 2;
   font-size: 11px;
-  color: #8b949e;
 }
-
-.history-entry__current {
-  color: #58a6ff;
-  font-weight: 500;
-}
-
-.history-entry__copy {
-  background: none;
-  border: none;
-  cursor: pointer;
-  font-size: 14px;
-  padding: 4px;
-}
-
-.history-entry__copy:hover {
-  opacity: 0.8;
+.history-entry__actions {
+  grid-row: 1 / 3;
+  grid-column: 2 / 3;
+  display: flex;
+  gap: 4px;
 }
 
 /* --- Type selection --- */