UBERF-13118: Send emails from Huly mail threads

[ArtyomSavchenko]

No description provided.

[Copilot]

Pull Request Overview

This PR implements functionality to send emails from Huly mail threads, extending the mail system to support bidirectional email communication. The primary purpose is to enable sending Huly messages as emails through the mail infrastructure.

• Renamed and restructured the inbound mail service to a more comprehensive mail worker
• Added outgoing email functionality with queue-based message processing
• Integrated email headers to prevent mail loops and identify Huly-generated messages

Reviewed Changes

Copilot reviewed 29 out of 46 changed files in this pull request and generated 7 comments.

Show a summary per file

File	Description
services/mail/pod-mail/src/main.ts	Enhanced validation and error logging for mail sending API
services/mail/pod-mail-worker/src/mailWorker.ts	New mail worker for processing outgoing Huly messages as emails
services/mail/pod-mail-worker/src/send.ts	Email sending functionality via HTTP API
services/mail/pod-mail-worker/src/workspaceClient.ts	Workspace client management with connection pooling
services/mail/pod-mail-worker/src/types.ts	Type definitions for mail messages and constants
services/mail/mail-common/src/utils.ts	Shared utilities for mail headers and Huly message detection
services/mail/mail-common/src/types.ts	Common type definitions and header constants
services/mail/mail-common/src/txHandler.ts	Transaction handling and recipient resolution logic
services/mail/mail-common/src/thread.ts	Thread lookup service with email-specific keys

Files not reviewed (1)

• common/config/rush/pnpm-lock.yaml: Language not supported