Fix console logging and message routing

Console Logging Improvements:
- Changed ConsoleRuntimeProvider to send logs immediately instead of batching
- Track pending send promises and await them in onCompleted callback
- Ensures REPL gets all logs before execution-complete
- Enables real-time console logging for HTML artifacts

Message Routing Fixes:
- Remove "handled" concept from message routing - broadcast all messages to all providers/consumers
- Change handleMessage return type from Promise<boolean> to Promise<void>
- Add debug logging to RuntimeMessageRouter to trace message flow
- Fix duplicate error logging (window error handler now only tracks errors, doesn't log them)

Output Formatting Consistency:
- Remove [LOG], [ERROR] prefixes from console output in both tools
- Show console logs before error messages
- Use "=> value" format for return values in both javascript-repl and browser-javascript
- Remove duplicate "Error:" prefix and extra formatting

Bug Fixes:
- Fix race condition where execution-complete arrived before console logs
- Fix ConsoleRuntimeProvider blocking execution-complete from reaching consumers
- Remove duplicate console log collection from SandboxedIframe
- Fix return value capture by wrapping user code in async function

packages/web-ui/src/components/sandbox/SandboxRuntimeProvider.ts

@@ -20,13 +20,12 @@ export interface SandboxRuntimeProvider {
 
 	/**
 	 * Optional message handler for bidirectional communication.
-	 * Return true if the message was handled, false to let other handlers try.
+	 * All providers receive all messages - decide internally what to handle.
 	 *
 	 * @param message - The message from the sandbox
 	 * @param respond - Function to send a response back to the sandbox
-	 * @returns true if message was handled, false otherwise
 	 */
-	handleMessage?(message: any, respond: (response: any) => void): Promise<boolean>;
+	handleMessage?(message: any, respond: (response: any) => void): Promise<void>;
 
 	/**
 	 * Optional documentation describing what globals/functions this provider injects.