feat(honcho): show clickable session line on CLI startup

Display a one-line Honcho session indicator with an OSC 8 terminal
hyperlink after the banner. Also shown when /title remaps the session.

agent/display.py

@@ -535,3 +535,46 @@ def get_cute_tool_message(
 
     preview = build_tool_preview(tool_name, args) or ""
     return _wrap(f"┊ ⚡ {tool_name[:9]:9} {_trunc(preview, 35)}  {dur}")
+
+
+# =========================================================================
+# Honcho session line (one-liner with clickable OSC 8 hyperlink)
+# =========================================================================
+
+_DIM = "\033[2m"
+_SKY_BLUE = "\033[38;5;117m"
+_ANSI_RESET = "\033[0m"
+
+
+def honcho_session_url(workspace: str, session_name: str) -> str:
+    """Build a Honcho app URL for a session."""
+    from urllib.parse import quote
+    return (
+        f"https://app.honcho.dev/explore"
+        f"?workspace={quote(workspace, safe='')}"
+        f"&view=sessions"
+        f"&session={quote(session_name, safe='')}"
+    )
+
+
+def _osc8_link(url: str, text: str) -> str:
+    """OSC 8 terminal hyperlink (clickable in iTerm2, Ghostty, WezTerm, etc.)."""
+    return f"\033]8;;{url}\033\\{text}\033]8;;\033\\"
+
+
+def honcho_session_line(workspace: str, session_name: str) -> str:
+    """One-line session indicator: `Honcho session: <clickable name>`."""
+    url = honcho_session_url(workspace, session_name)
+    linked_name = _osc8_link(url, f"{_SKY_BLUE}{session_name}{_ANSI_RESET}")
+    return f"{_DIM}Honcho session:{_ANSI_RESET} {linked_name}"
+
+
+def write_tty(text: str) -> None:
+    """Write directly to /dev/tty, bypassing stdout capture."""
+    try:
+        fd = os.open("/dev/tty", os.O_WRONLY)
+        os.write(fd, text.encode("utf-8"))
+        os.close(fd)
+    except OSError:
+        sys.stdout.write(text)
+        sys.stdout.flush()