Allow SOCKS proxy to be supplied via http_proxy env var

[normanr]

Description

http_proxy (or HTTP_PROXY) environment variable protocol is currently ignored, and the connection fails if socks://host:port is supplied. This change just populates proxyType from the regular expression capture for proto://, which is good enough to allow the existing useSocksProxy logic to work (once it's moved below the env var processing).

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• This change requires a documentation update

How Has This Been Tested?

I tested manually with http_proxy=socks://localhost:1080 ./build/unix/src/stellarium with and without the change. I checked that the qDebug() log message changed appropriately and that the Satellites plugin could successfully retrieve files via the proxy.

Test Configuration:

• Operating system: Debian Linux
• Graphics Card: Intel(R) UHD Graphics 620

Checklist:

• My code follows the code style of this project.
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation (header file)
• I have updated the respective chapter in the Stellarium User Guide
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules

[github-actions]

Great PR! Please pay attention to the following items before merging:

Files matching src/**/*.cpp:

• Are possibly unused includes removed?

This is an automatically generated QA checklist based on modified files.

[github-actions]

Thanks for adding your first pull request to Stellarium. If you have questions, please do not hesitate to contact us.

[alex-w]

Thanks!

[gzotti]

I never used or even set up a proxy, cannot technically comment on this. If it works better than before, fine for me.

[github-actions]

Hello @normanr!

Please check the fresh version (development snapshot) of Stellarium:
https://github.com/Stellarium/stellarium-data/releases/tag/weekly-snapshot

[github-actions]

Hello @normanr!

Please check the latest stable version of Stellarium:
https://github.com/Stellarium/stellarium/releases/latest