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/lib/urlDetector.ts

@@ -0,0 +1,78 @@
+/**
+ * Detects long URLs that span multiple hard-wrapped lines in PTY output.
+ *
+ * The Linux PTY hard-wraps long lines with \r\n at the terminal column width,
+ * which breaks xterm.js WebLinksAddon URL detection. This class reassembles
+ * those wrapped URLs and fires a callback for ones >= 100 chars.
+ */
+
+const ANSI_RE =
+  /\x1b(?:\[[0-9;?]*[A-Za-z]|\][^\x07\x1b]*(?:\x07|\x1b\\)?|[()#][A-Za-z0-9]|.)/g;
+
+const MAX_BUFFER = 8 * 1024; // 8 KB rolling buffer cap
+const DEBOUNCE_MS = 300;
+const MIN_URL_LENGTH = 100;
+
+export type UrlCallback = (url: string) => void;
+
+export class UrlDetector {
+  private decoder = new TextDecoder();
+  private buffer = "";
+  private timer: ReturnType<typeof setTimeout> | null = null;
+  private lastEmitted = "";
+  private callback: UrlCallback;
+
+  constructor(callback: UrlCallback) {
+    this.callback = callback;
+  }
+
+  /** Feed raw PTY output chunks. */
+  feed(data: Uint8Array): void {
+    this.buffer += this.decoder.decode(data, { stream: true });
+
+    // Cap buffer to avoid unbounded growth
+    if (this.buffer.length > MAX_BUFFER) {
+      this.buffer = this.buffer.slice(-MAX_BUFFER);
+    }
+
+    // Debounce — scan after 300 ms of silence
+    if (this.timer !== null) clearTimeout(this.timer);
+    this.timer = setTimeout(() => {
+      this.timer = null;
+      this.scan();
+    }, DEBOUNCE_MS);
+  }
+
+  private scan(): void {
+    const clean = this.buffer.replace(ANSI_RE, "");
+    const lines = clean.replace(/\r\n/g, "\n").replace(/\r/g, "\n").split("\n");
+
+    for (let i = 0; i < lines.length; i++) {
+      const match = lines[i].match(/https?:\/\/[^\s'"]+/);
+      if (!match) continue;
+
+      // Start with the URL fragment found on this line
+      let url = match[0];
+
+      // Concatenate subsequent continuation lines (non-empty, no spaces, no leading whitespace)
+      for (let j = i + 1; j < lines.length; j++) {
+        const next = lines[j];
+        if (!next || next.startsWith(" ") || next.includes(" ")) break;
+        url += next;
+        i = j; // skip this line in the outer loop
+      }
+
+      if (url.length >= MIN_URL_LENGTH && url !== this.lastEmitted) {
+        this.lastEmitted = url;
+        this.callback(url);
+      }
+    }
+  }
+
+  dispose(): void {
+    if (this.timer !== null) {
+      clearTimeout(this.timer);
+      this.timer = null;
+    }
+  }
+}