Mitigate Jekyll local build issues with Docker-first workflow

[Flamki]

Summary
Reduce day-to-day Jekyll setup friction by documenting and prioritizing a reproducible Docker workflow, plus remove an unnecessary gem dependency that can trigger native build failures.

What this changes

• Make Docker the recommended local development path in README.
• Keep native Ruby setup as an optional path.
• Update docs-meta overview accordingly.
• Add troubleshooting guidance for native gem extension failures (sassc/google-protobuf/ffi/stringio).
• Remove explicit open-uri Gemfile dependency and rely on Ruby stdlib open-uri for the citation plugin.

Why
This addresses part of #471 with a low-risk mitigation while migration exploration in #472 continues.

Validation

• pre-commit run --files Gemfile README.md content/docs/docs-meta/docs-meta-overview.md content/docs/docs-meta/docs-meta-common-issues.md
• dockerized Jekyll build via jekyll/jekyll:4 completed successfully

Relates to #471
Context: #472

[hanzalahwaheed]

hey! I think this is something that is planned to be addressed later as the org plans to migrate to Hugo.