feat(cli): terminal tab titles + desktop notifications for agent state

[Jpalmer95]

Summary

Add terminal tab title updates and optional OS-level desktop notifications so users with multiple terminal tabs can see at a glance which Hermes session needs attention.

The Problem

When running multiple Hermes instances in different terminal tabs/instances, users have no way to tell which session needs their input without tab-switching. The agent may be waiting for command approval, a clarify answer, or may have hit an error — but the user can't see this without focusing the right tab.

The Solution

Two complementary notification mechanisms, both off by default:

1. Terminal Tab Titles (lightweight, recommended first step)

Updates the terminal emulator's window/tab title bar using standard OSC escape sequences, reflecting the agent's current state:

• Hermes - Ready — waiting for input
• Hermes - Thinking... — calling the LLM
• Hermes - Using tool: terminal — executing a tool
• Hermes - Waiting for approval — command approval needed
• Hermes - Has a question for you — agent clarified
• Hermes - Error — API/tool failure

Works in GNOME Terminal, iTerm2, Alacritty, Kitty, Windows Terminal, WezTerm, and tmux (with set-titles on).

2. Desktop Notifications (optional)

Native OS notifications appearing in the system notification tray:

• Linux: notify-send (freedesktop.org)
• macOS: osascript
• Windows: PowerShell WinRT toast

Usage

Config (permanent):

display:
  notifications:
    enabled: true       # Master switch — enables tab titles
    tab_title: true     # Update terminal tab title on state changes
    desktop: false      # Send OS notification tray popups
    events:
      approval: true
      clarify: true
      error: true
      turn_complete: false

In-session (/notif command):

/notif                  # Show current status
/notif on               # Enable all notifications
/notif off              # Disable all notifications
/notif tab [on|off]     # Toggle tab title updates
/notif desktop [on|off] # Toggle OS notifications

Files Changed

File	What
agent/notification.py	New — cross-platform desktop notification helpers
agent/display.py	Notification config globals, init_notifications(), set_tab_title(), KawaiiSpinner start/stop hooks
cli.py	Init at startup, wire into approval/clarify/turn-complete, _handle_notif_command()
hermes_cli/config.py	display.notifications config section with defaults
hermes_cli/commands.py	/notif slash command registration
tests/agent/test_notification.py	25 tests covering all modules

Cross-Platform

• Windows-safe: platform.system() guards, shutil.which() checks, PowerShell escaping
• Headless-safe: skips notifications when no DISPLAY/Wayland session is present
• Non-TTY-safe: tab titles only emit when stdout is a real terminal
• Best-effort: no exceptions propagate into the agent loop

Tests

25 new tests, all passing:

• Desktop notification (build commands per platform, helpers, enabled/disabled)
• Display notification config (init, tab title output)
• KawaiiSpinner integration (start/stop title updates)
• Config defaults (structure, disabled by default)
• Command registration (/notif in registry)

python -m pytest tests/agent/test_notification.py -v — 25/25 passed.

[alt-glitch]

Duplicate of #5318 — earliest open PR implementing terminal tab title updates (#5505). This adds desktop notifications on top but the core OSC title feature is the same.

[teknium1]

Thanks for the cross-platform implementation. The underlying classic-CLI need remains: current main's automatic title path is TUI-only (ui-tui/src/app/useMainApp.ts:576-586), so this is not redundant.

Problems

• hermes_cli/config.py:978 adds display.notifications.events, but the diff's init_notifications() only accepts enabled, tab_title, and desktop; no production path consumes the four event flags. In particular, agent/notification.py defines notify_error() but the changed cli.py paths do not call it.
• agent/display.py clears the title on spinner stop, while the PR documents a Hermes - Ready idle title.
• hermes_cli/commands.py drops cli_only=True from the existing /indicator entry without implementing or testing gateway behavior for it.

Suggested changes

• Make each configured event gate its corresponding emission, including an actual classic-CLI error path, and cover suppression behavior in tests.
• Restore the documented ready title at turn completion.
• Restore /indicator as CLI-only unless its broader availability is intentional and covered.

Automated hermes-sweeper review.

[teknium1]

These event flags are not consumed by the added runtime: init_notifications() only receives enabled/tab_title/desktop, and the changed CLI paths do not read approval, clarify, error, or turn_complete. Please thread these controls into each notification emission or remove them.

[OutThisLife]

Superseded by #74654 (classic CLI) and #74683 (TUI). The core OSC tab title feature is covered by #74654; the desktop notifications this PR adds on top are out of scope for the title feature. Closing to consolidate.