wiki: redirect everything to go.dev/wiki For #61940.
fix GetCounter method returns
Missing "rare", I think
url updates to go.dev / pkg.go.dev
Updated CodeReviewConcurrency (markdown)
Some advice here is incorrect. Add warning and disputed notices.
Add a link to "Rethinking Classical Concurrency Patterns" video
Add a link to https://songlh.github.io/paper/go-study.pdf
Add CodeReviewConcurrency page