feat: choose which probes link to which agents from the admin

The panel decides the probe/agent pairs and probes always dial out. A new
fleet.auto_link setting connects every probe to every agent (default); with it
off only the pairs chosen by hand connect, and any pair can be forced on or
off. The Probes page has a link matrix with the switch and per-pair toggles.

web/display/src/display.css

@@ -1205,19 +1205,11 @@ input {
 }
 
 /* 版本、tag：等宽的小字 */
-.fact .v.mono-tag,
-.probe-tag {
+.fact .v.mono-tag {
   font-family: var(--font-mono);
   font-size: 11px;
 }
 
-.probe-tag {
-  padding: 0 6px;
-  border-radius: 6px;
-  background: color-mix(in srgb, var(--app-ink) 6%, transparent);
-  color: var(--app-ink-muted);
-}
-
 .build-info {
   display: flex;
   flex-wrap: wrap;
@@ -1227,3 +1219,35 @@ input {
   font-family: var(--font-mono);
   font-size: 11px;
 }
+
+/* 总览卡片里的线路标题：名字太长就省略号，右边只放一个短标签，不换行 */
+.line-top {
+  min-width: 0;
+}
+
+.line-top .line-name {
+  flex: 1 1 auto;
+  min-width: 0;
+  white-space: nowrap;
+}
+
+.line-top .line-name .arrow {
+  flex: none;
+}
+
+.line-top .line-name .name {
+  min-width: 0;
+  overflow: hidden;
+  text-overflow: ellipsis;
+}
+
+.line-top .line-name .flag,
+.line-top .line-name .isp {
+  flex: none;
+}
+
+.line-top .line-range,
+.line-top .chip {
+  flex: none;
+  white-space: nowrap;
+}