feat(notifier): make notifier system robust with manual harness and desktop setup

[whoisasx]

Summary

• Adds ao notify test as a manual notifier playground for realistic demo notifications without spawning sessions, starting AO, touching tmux, or creating worktrees.
• Supports templates, explicit targets, priority routes, all-target delivery, actions, JSON data overrides, dry-run/JSON output, and a local in-memory webhook sink.
• Refactors ao doctor --test-notify onto the shared notifier harness with the basic template.
• Improves macOS desktop notifications by preferring click-to-open delivery and adding ao setup desktop for an explicit native AO Notifier.app install/config flow.
• Adds a macOS notifier app package, config wiring for notifiers.desktop.backend: ao-app, and fallback delivery through terminal-notifier then osascript.
• Handles denied macOS notification permission with a clean setup error and System Settings instructions instead of a raw Node stack trace.
• Updates the Composio notifier adapter to support legacy executeAction(), current SDK getEntity(...).execute(), and raw actions.execute() clients.
• Sends Composio Slack messages using the documented markdown_text field, normalizes #channel names, and adds actionable guidance when no active Composio connection exists.

Closes #1579

Test plan

• pnpm --filter @aoagents/ao-notifier-macos build
• pnpm --filter @aoagents/ao-plugin-notifier-desktop test
• pnpm --filter @aoagents/ao-plugin-notifier-composio test
• pnpm --filter @aoagents/ao-plugin-notifier-composio typecheck
• pnpm --filter @aoagents/ao-plugin-notifier-composio build
• pnpm --filter @aoagents/ao-integration-tests test -- notifier-composio.integration.test.ts
• pnpm --filter @aoagents/ao-integration-tests typecheck
• pnpm --filter @aoagents/ao-cli test
• pnpm --filter @aoagents/ao-cli test -- setup.test.ts
• pnpm --filter @aoagents/ao-cli typecheck
• pnpm --filter @aoagents/ao-cli build
• pnpm typecheck
• pnpm build

Notes

• ao setup desktop is explicit; npm/global install does not silently install the macOS app.
• Live Composio harness execution now reaches the SDK and reports missing Slack connection setup clearly: connect Slack in Composio, or set notifiers.composio.connectedAccountId / entityId.
• pnpm build succeeds with existing web build warnings for optional @composio/core resolution in tracker-linear and an existing non-null assertion warning in useXtermTerminal.ts.

[github-actions]

Test Coverage Report

Changed files have no coverage data (not instrumented or no tests ran).