[Feature request]: Allow Filtering Workflow Notification Emails by Environment

### Problem Statement

### Description

Currently, Sentry’s Workflow Notification Settings page does not provide an option to filter or silence notification emails based on environment. As a result, teams receive notifications for every issue across all environments, even when those issues originate from non-production environments that may not require immediate attention.

### Customer Feedback:

“Currently, every team is assigned to a certain parts of the projects and once Sentry reports the issue it is sent to everyone in that team. The issue is that even if someone is testing the sandbox (not production environment) everyone in the team gets those issues as well reported in the email. As a result, there are tons of emails sent with issues that are not related to the live site.”

### Solution Brainstorm

_No response_

### Product Area

Issues

Start by locating the Workflow Notification Settings page and the notification-email handling for the Issues product area. Define how environment filtering or silencing should work, then verify that notifications can be limited to the intended environments and that the behavior is covered by relevant tests.

Written by the indexing model from the issue text.