Upgrade Electron to LTS version

[Nick-Lucas]

As of now there are lots of blockers to upgrading to the latest electron, and 11 is currently the highest possible

Electron 14/15: node-pty does not support context aware native modules and there is no workaround currently

microsoft/node-pty#405

Possible workaround is to run node-pty in the main process or similar, and use electron's IPC to channel communication. This may be a good idea anyway to improve on performance.

Electron v12-13: Major performance regression when using "spawn" on MacOS

electron/electron#26143

This is due to an upstream issue in libuv and a breaking change on MacOS causing a large chunk of memory to be copied into the new process. Fixing it has been causing the maintainers of the whole chain problems.

Possible fixes include moving spawn calls to the main process or similar, and using electron's IPC to make the requests and responses. May also help with performance. electron/electron#26143 (comment)

[Nick-Lucas]

Branch 931764a (chore/electron-upgrade) is tracking attempts to upgrade

[Nick-Lucas]

Branch 9600b8a (chore/electron-11) also tracks an electron 11 attempt as some reports indicated this could still work. In Dev it appears fine, but an unsigned production build is not fine