feat(agentic-os): add unified ControlHub, Playbook system, and CDP browser control

[bobleer]

Summary

Transform BitFun from an AI IDE into an Agentic OS by introducing a unified control architecture:

• ControlHub tool — single entry point for all control operations, routing by domain (desktop, browser, app, terminal, system) to existing backends (ComputerUse, SelfControl, TerminalControl) and new capabilities. Existing tools are retained for backward compatibility.
• Playbook tool — YAML-based predefined operation playbooks for common tasks (browser screenshot, data extraction, form fill, desktop automation, model setup). Supports template variable substitution with automatic type preservation, conditional step filtering, and output variable annotations.
• CDP browser control — connect to and control the user's default browser (Chrome, Edge, etc.) via Chrome DevTools Protocol, preserving login sessions, cookies, and extensions. Includes CdpClient (WebSocket transport), BrowserLauncher (cross-platform detection + CDP-enabled launch), BrowserActions (navigate, click, fill, snapshot, screenshot, evaluate JS, etc.), and Tauri desktop API commands.
• Frontend UI — SessionConfig adds a browser control section with CDP status, connect button, and create-launcher button (macOS). All toast messages use i18n (en-US + zh-CN).

Key Design Decisions

1. Backward compatible — ComputerUse, SelfControl, and TerminalControl tools remain registered; ControlHub is an additive unified layer.
2. Atomic actions — all control operations are fine-grained atomic actions that agents can compose freely or follow Playbook guides.
3. Type-safe templates — Playbook {{var}} substitution preserves native JSON types (numbers, booleans) instead of always producing strings.
4. Condition engine — Playbook steps support "X is Y", "X is not Y", "X is provided" conditions for conditional execution.
5. Cross-platform — system.open_app works on macOS (open -a), Windows (cmd /C start), and Linux (xdg-open).

Files Changed

Area	Files	Description
Browser control	browser_control/ (4 files)	CDP client, browser launcher, high-level actions
ControlHub	control_hub_tool.rs	Unified routing tool (~725 lines)
Playbook	playbook_tool.rs + builtin_playbooks/ (5 YAML)	Playbook engine + built-in templates
Tool registry	registry.rs, mod.rs	Register new tools
Desktop API	browser_control_api.rs, lib.rs	Tauri commands for browser control
Frontend	SessionConfig.tsx	Browser control UI section
i18n	session-config.json (en-US, zh-CN)	Localization strings

Test Plan

• cargo check passes with zero errors and warnings
• npx tsc --noEmit passes for web-ui
• Desktop app: verify browser control section appears in Session Config
• Desktop app: click "Connect browser" with a running Chrome/Edge — verify CDP connection
• Agent: test ControlHub { domain: "browser", action: "connect" } → navigate → snapshot flow
• Agent: test Playbook { action: "run", name: "browser_screenshot", params: { url: "https://example.com" } }
• Agent: test ControlHub { domain: "system", action: "open_app", app_name: "Calculator" }
• Verify existing ComputerUse / SelfControl tools still work independently