Improve documentation for proxy configuration and connection setup

[beltagymohamed]

Description

• Clarified the process of running the proxy container with the experimental feature EXP_SERVER_SIDE_SDK_CONFIG_TOKENS.
• Added instructions for replacing placeholders with actual values.
• Provided clear code examples for both running the proxy and connecting to it.

Fixes # (issue)

Type of change

Please delete options that are not relevant.

• 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 not work as expected)
• This change requires a documentation update

How Has This Been Tested?

Please describe the tests that you ran to verify your changes.

• Manual Tests: Verified that the updated documentation correctly explains the setup process and is easy to follow. All examples were tested manually for accuracy.

Checklist:

• My code follows the style guidelines 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
• 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

[coveralls]

coverage: 95.316%. remained the same
when pulling 70ac9d3 on beltagymohamed:patch-1
into 3d36c6d on Unleash:main.

[FredrikOseberg]

@beltagymohamed

Hello, and thank you for this PR!

The unleash-proxy is in maintenance mode. We recommend using unleash-edge instead. Therefore, I'm reluctant to merge this PR as we don't want to put more focus on the proxy.

Appreciate the effort you put into this.

[beltagymohamed]

@FredrikOseberg

Thank you for your review! I understand that the unleash proxy is in maintenance mode and that the focus is shifting to unleash edge. However, I wanted to ask: GitLab's feature flagging system currently relies on the proxy. Can we continue using GitLab feature flags reliably, or will the discontinuation of the proxy impact this functionality?

[FredrikOseberg]

@FredrikOseberg

Thank you for your review! I understand that the unleash proxy is in maintenance mode and that the focus is shifting to unleash edge. However, I wanted to ask: GitLab's feature flagging system currently relies on the proxy. Can we continue using GitLab feature flags reliably, or will the discontinuation of the proxy impact this functionality?

@beltagymohamed

We will continue to support the proxy and provide security patches, but we won't develop new functionality in the proxy. You don't need to worry about support being dropped for gitlab.

[beltagymohamed]

@FredrikOseberg Thanks for clarification for now to don't totally lose this info I added it to the repo docs #340