x/tools: plan for generic methods

[adonovan]

If #77273 is accepted, we will need to update the entire x/tools repo to ensure that gopls, vulncheck, and various other tools and libraries work with the new syntax before go1.27. The task of this issue is to audit the repo and gather a clear set of tasks as subissues, and keep track as we work through them.

[gabyhelp]

Related Issues

• all: audit x/ repos for gotypesalias settings #69772 (closed)
• tools: track tools/tooling updates to support generics #50558

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