Add toast notification for wrapped long URLs in terminal

PTY hard-wraps long URLs (e.g. OAuth) with \r\n at column width, breaking
xterm.js link detection. This adds a UrlDetector that reassembles wrapped
URLs from the output stream and shows a non-intrusive floating toast with
an "Open" button. Auto-dismisses after 30s, no terminal layout impact.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/src/components/terminal/UrlToast.tsx

@@ -0,0 +1,101 @@
+interface Props {
+  url: string;
+  onOpen: () => void;
+  onDismiss: () => void;
+}
+
+export default function UrlToast({ url, onOpen, onDismiss }: Props) {
+  return (
+    <div
+      className="animate-slide-down"
+      style={{
+        position: "absolute",
+        top: 12,
+        left: "50%",
+        transform: "translateX(-50%)",
+        zIndex: 40,
+        display: "flex",
+        alignItems: "center",
+        gap: 10,
+        padding: "8px 12px",
+        background: "var(--bg-secondary)",
+        border: "1px solid var(--border-color)",
+        borderRadius: 8,
+        boxShadow: "0 4px 12px rgba(0,0,0,0.4)",
+        maxWidth: "min(90%, 600px)",
+      }}
+    >
+      <div style={{ flex: 1, minWidth: 0 }}>
+        <div
+          style={{
+            fontSize: 12,
+            color: "var(--text-secondary)",
+            marginBottom: 2,
+          }}
+        >
+          Long URL detected
+        </div>
+        <div
+          style={{
+            fontSize: 12,
+            fontFamily: "monospace",
+            color: "var(--text-primary)",
+            overflow: "hidden",
+            textOverflow: "ellipsis",
+            whiteSpace: "nowrap",
+          }}
+        >
+          {url}
+        </div>
+      </div>
+
+      <button
+        onClick={onOpen}
+        style={{
+          padding: "4px 12px",
+          fontSize: 12,
+          fontWeight: 600,
+          color: "#fff",
+          background: "var(--accent)",
+          border: "none",
+          borderRadius: 4,
+          cursor: "pointer",
+          whiteSpace: "nowrap",
+          flexShrink: 0,
+        }}
+        onMouseEnter={(e) =>
+          (e.currentTarget.style.background = "var(--accent-hover)")
+        }
+        onMouseLeave={(e) =>
+          (e.currentTarget.style.background = "var(--accent)")
+        }
+      >
+        Open
+      </button>
+
+      <button
+        onClick={onDismiss}
+        style={{
+          padding: "2px 6px",
+          fontSize: 14,
+          lineHeight: 1,
+          color: "var(--text-secondary)",
+          background: "transparent",
+          border: "none",
+          borderRadius: 4,
+          cursor: "pointer",
+          flexShrink: 0,
+        }}
+        onMouseEnter={(e) =>
+          (e.currentTarget.style.color = "var(--text-primary)")
+        }
+        onMouseLeave={(e) =>
+          (e.currentTarget.style.color = "var(--text-secondary)")
+        }
+        aria-label="Dismiss"
+      >
+        ✕
+      </button>
+    </div>
+  );
+}