feat: add extension-to-BrowserManager finalize ack

[vringar]

Summary

Replaces the fixed sleep in FinalizeCommand with a bidirectional ack from the WebExtension. When the extension finishes processing a Finalize message (forwarding to StorageController, clearing visitID), it sends a FinalizeAck response back on the same TCP connection. Python reads this ack instead of sleeping.

• Make the privileged sockets API bidirectional: open outputStream on accepted connections, add sendResponse() API, pass connectionId through onDataReceived
• Extension sends FinalizeAck after processing Finalize in loggingdb.ts
• Add receive() method to ClientSocket in socket_interface.py
• FinalizeCommand waits for ack with timeout fallback (0.5s test / 5s prod)

Stacked on #1128.

[Copilot]

Pull request overview

This PR replaces a fixed sleep in the FinalizeCommand with a bidirectional acknowledgment from the WebExtension. Instead of sleeping for a fixed duration, Python now waits for the extension to send a FinalizeAck response after processing the Finalize message, improving reliability and reducing unnecessary wait time.

Changes:

• Added bidirectional socket communication support by implementing response functionality in the privileged sockets API
• Extension now sends FinalizeAck after processing Finalize messages
• Python's FinalizeCommand waits for acknowledgment with configurable timeout instead of using fixed sleep

Reviewed changes

Copilot reviewed 6 out of 7 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
openwpm/socket_interface.py	Added receive() and _receive_bytes() methods to read acknowledgment messages from the socket
openwpm/commands/browser_commands.py	Replaced fixed sleep with receive() call to wait for finalize acknowledgment with timeout fallback
Extension/src/types/browser.d.ts	Added TypeScript type definitions for ConnectionId and sendResponse API
Extension/src/socket.ts	Modified to pass connectionId and create respond function for sending responses
Extension/src/loggingdb.ts	Added logic to send FinalizeAck response after processing Finalize message
Extension/bundled/privileged/sockets/schema.json	Added schema definition for sendResponse function and connectionId parameter
Extension/bundled/privileged/sockets/api.js	Implemented bidirectional socket support with output streams and connection tracking

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[Copilot]

The default timeout of 5.0 seconds in receive() is inconsistent with how it's called in FinalizeCommand, where the timeout is explicitly passed based on testing mode. Consider removing the default value to make timeout specification mandatory and prevent accidental misuse with an unintended default.

Suggested change

	def receive(self, timeout: float = 5.0) -> Any:
	def receive(self, timeout: float) -> Any:

[Copilot]

Catching bare Exception is too broad and will mask unexpected errors like KeyboardInterrupt or programming errors. Catch specific exceptions like socket.timeout or RuntimeError that are expected from the receive() operation.

[Copilot]

Connection cleanup only happens when the socket closes abnormally. Normal connection closure (when available bytes becomes 0) should also delete the connectionId from the map to prevent memory leaks from accumulating stale connections.