tools: add pubmed tool

[longkeyy]

PR Checklist

• [Y] Read the Contributing documentation.
• [Y] Read the Code of conduct documentation.
• [Y] Name your Pull Request title clearly, concisely, and prefixed with the name of the primarily affected package you changed according to Good commit messages (such as memory: add interfaces for X, Y or util: add whizzbang helpers).
• [Y] Check that there isn't already a PR that solves the problem the same way to avoid creating a duplicate.
• [Y] Provide a description in this PR that addresses what the PR is solving, or reference the issue that it solves (e.g. Fixes #123).
• [Y] Describes the source of new concepts.
• [Y] References existing implementations as appropriate.
• [Y] Contains test coverage for new functions.
• [Y] Passes all golangci-lint checks.

Fixes #1043