Github services have to be signed into separately

System details:

Positron and OS details:

Positron Version: 2025.08.0 build 108
Code - OSS Version: 1.102.0
Commit: 2ae1981311adc4d035e117cf2d1cdf164b5b8ae8
Date: 2025-07-30T03:42:26.399Z
Electron: 35.6.0
Chromium: 134.0.6998.205
Node.js: 22.15.1
V8: 13.4.114.21-electron.0
OS: Darwin arm64 24.5.0

Session details:

NA

Describe the issue:

Positron has various components that require Github authentication. These do not all use the same auth service, and consequently it is necessary to sign into Github multiple times from Positron to enable them all.

Steps to reproduce the issue:

Sign in to Github on the Add Language Model screen.

Then, try to use Github Pull Requests. It must be signed into Github separately:

Expected or desired behavior:

Signing into Github one time should be enough. This goes for all 3 Github integration points:

1. Github Copilot completions
2. Github Copilot chat (soon; #2010)
3. Github Pull Requests

Because the github-authentication extension provides the nice account UX and sign in / sign out affordances in the activity bar, it would be ideal if all three mechanisms used that to initiate sign-in and supply Github credentials.

Start by tracing the github-authentication extension and the three named integration points: GitHub Copilot completions, Copilot chat, and GitHub Pull Requests. Done means signing in through the shared account UI supplies credentials to all three without separate GitHub sign-ins.