feat(hands): add Browser Hand for web automation

Add BrowserHand implementation with:
- BrowserAction enum for all automation actions
- Navigate, Click, Type, Scrape, Screenshot, FillForm
- Wait, Execute (JavaScript), GetSource, GetUrl, GetTitle
- Scroll, Back, Forward, Refresh, Hover, PressKey, Upload
- Hand trait implementation with config and execute
- Integration with existing Tauri browser commands

Browser Hand enables agents to interact with web pages
for navigation, form filling, scraping, and automation.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

crates/zclaw-hands/src/hands/mod.rs

@@ -0,0 +1,20 @@
+//! Educational Hands - Teaching and presentation capabilities
+//!
+//! This module provides hands for interactive classroom experiences:
+//! - Whiteboard: Drawing and annotation
+//! - Slideshow: Presentation control
+//! - Speech: Text-to-speech synthesis
+//! - Quiz: Assessment and evaluation
+//! - Browser: Web automation
+
+mod whiteboard;
+mod slideshow;
+mod speech;
+mod quiz;
+mod browser;
+
+pub use whiteboard::*;
+pub use slideshow::*;
+pub use speech::*;
+pub use quiz::*;
+pub use browser::*;