Motivation

To make the buffer mechanism of the output panel more robust.

Change description

Uses a setTimeout rather that setInterval in our buffer, this ensures that flush calls do not interfere with each other. On disposing our buffer we set a boolean flag to prevent additional setTimeout callbacks from being created, if there is a setTimeout callback in progress when the buffer is "disposed" it will complete before running flush a final time to be exhaustive.

gRPC errors are also added to the buffer, to ensure proper ordering in the output panel.

Reviewer checklist

• PR addresses a single concern.
• The PR has no duplicates (please search among the Pull Requests before creating one)
• PR title and description are properly filled.
• Docs have been added / updated (for bug fixes / features)