ISSUE-17098: PIP-199: Create a robust and inline Client Feature Matrix page

[sijie]

Original Issue: apache#17098

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Motivation

As the outcome of PIP-108, the Client Feature Matrix has addressed the initial user request for technology evaluation and selection. It has been linked on Pulsar doc site, providing an overview of feature supportability on language-specific clients.

However, it has the following limitations to continually serving the purpose over time:

1. Visibility: Not prominent for users/maintainers to notice it.
2. Process control: No required review/approval or version control.
3. Accuracy: A bit out-of-dated with limited chances to get it updated (possibly caused by 1&2).

As an extension/enhancement to PIP-108, this proposal aims to make the existing client feature matrix more robust and prominent to address the above pain points and better serve the adoption purpose.

Goal

To better serve the adoption purpose, I think we can make the following improvements to make it more robust and prominent:

1. Deliver a more robust Client Feature Matrix and required documentation through a thorough review and update.
   ----@RobertIndie and @shibd will be working on adding the information for missing features and supportability in language-specific clients.
2. Move the matrix to the codebase (Pulsar repo) and display it inline on a web page to provide a better reading experience. Reference. ---- @zeo1995 is researching it.

A quick question is about the granularity of the feature sets presented in the new matrix. Generally, we have two options:

• Display a full version as we do in the existing feature matrix to provide more detailed tech capabilities.
• Display a compact version with high-level features to provide better readability.

Implementation

As discussed with @urfreespace, it is feasible and the community can maintain the matrix by modifying a JSON file.
Details will be added as soon as it is fully discussed in the community.