fix(ui): align agent auth selection styling with home protocol tabs

- Use a subtle accent background instead of an outlined selected state
- Keep selection styling consistent across light, dark, and hover states

src/styles/feature-pages.css

@@ -3243,11 +3243,13 @@
   background: var(--theme-e8e5dc);
   color: var(--theme-2d2a26);
 }
-.agent-auth-segmented-button.active {
-  background: var(--theme-fffdf8);
-  color: var(--theme-2d2a26);
+.agent-auth-segmented-button.active,
+.agent-auth-segmented-button.active:hover:not(:disabled) {
+  background: color-mix(in srgb, var(--ui-accent) 10%, var(--bg-card));
+  color: var(--ui-accent);
+  border-color: transparent;
   font-weight: var(--font-weight-semibold);
-  box-shadow: 0 1px 3px rgba(45, 42, 38, 0.12);
+  box-shadow: none;
 }
 .agent-auth-segmented-button:disabled {
   cursor: not-allowed;

src/styles/workspace-white.css

@@ -63,7 +63,7 @@
 }
 
 :root:not([data-theme='dark']) .workspace :is(
-  .agent-list-items button.active, .agent-auth-segmented-button.active,
+  .agent-list-items button.active,
   .routing-segmented button.active, .plugin-tabs button.active,
   .usage-analysis-metric button[aria-pressed='true']
 ) {
@@ -93,6 +93,15 @@
   color: var(--ui-accent-strong);
 }
 
+/* Match the home protocol selection, including while hovered. */
+:root:not([data-theme='dark']) .workspace .agent-auth-segmented-button.active,
+:root:not([data-theme='dark']) .workspace .agent-auth-segmented-button.active:hover:not(:disabled) {
+  background: color-mix(in srgb, var(--ui-accent) 10%, var(--bg-card));
+  border-color: transparent;
+  color: var(--ui-accent);
+  box-shadow: none;
+}
+
 /* Do not let local subpage palettes bring the neutral fills back. */
 :root:not([data-theme='dark']) .workspace .usage-tab-panel {
   --usage-page-soft: #fff;