feat: comprehensive console capture and offline mode support

Major enhancements to browser automation and debugging capabilities:

**Console Capture Features:**
- Add console output file option (CLI, env var, session config)
- Enhanced CDP console capture for service worker messages
- Browser-level security warnings and mixed content errors
- Network failure and loading error capture
- All console contexts written to structured log files
- Chrome extension for comprehensive console message interception

**Offline Mode Support:**
- Add browser_set_offline tool for DevTools-equivalent offline mode
- Integrate offline mode into browser_configure tool
- Support for testing network failure scenarios and service worker behavior

**Extension Management:**
- Improved extension installation messaging about session persistence
- Console capture extension with debugger API access
- Clear communication about extension lifecycle to MCP clients

**Technical Implementation:**
- CDP session management across multiple domains (Runtime, Network, Security, Log)
- Service worker context console message interception
- Browser context factory integration for offline mode
- Pure Chromium configuration for optimal extension support

All features provide MCP clients with powerful debugging capabilities
equivalent to Chrome DevTools console and offline functionality.

src/browserContextFactory.ts

@@ -72,6 +72,12 @@ class BaseContextFactory implements BrowserContextFactory {
     testDebug(`create browser context (${this.name})`);
     const browser = await this._obtainBrowser();
     const browserContext = await this._doCreateContext(browser, extensionPaths);
+    
+    // Apply offline mode if configured
+    if ((this.browserConfig as any).offline !== undefined) {
+      await browserContext.setOffline((this.browserConfig as any).offline);
+    }
+    
     return { browserContext, close: () => this._closeBrowserContext(browserContext, browser) };
   }