add a CI check that the readme file is up-to-date

[devoncarew]

• add a CI check that the readme file is up-to-date
• address Add a test to ensure tool list in README is up to date #172

Note that this PR also changes the format of the list of tools; it adds some categorization (we have a bunch of tools now); https://github.com/dart-lang/ai/blob/f8fb7408f39ac9dfa1d83ad0ebb4b0934e2cd8a9/pkgs/dart_mcp_server/README.md .

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[github-actions]

PR Health

Changelog Entry ✔️

Package	Changed Files

Changes to files need to be accounted for in their respective changelogs.

[devoncarew]

Hmm, it looks like dart pub get for this package takes 1m 52s. I expect that's due to the git dep on the dart-lang/sdk repo (to get the language_server_protocol package).

[kenzieschmoll]

nit: consider looping through this list in the initialize method so that it is less likely a new tool is added to initialize and not added here. You'd have to store that tools with their associated callback here.

[kenzieschmoll]

nit: use cascades

[jakemac53]

Hmm, it looks like dart pub get for this package takes 1m 52s. I expect that's due to the git dep on the dart-lang/sdk repo (to get the language_server_protocol package).

Yeah it is, no good way to avoid it that I am aware of. We could depend on a specific hash and that might get us a cache hit (if we also cache the pub cache on GitHub actions), so it would speed up CI a fair bit.

[jakemac53]

You could just merge this into the job above to avoid the extra setup work 🤷‍♂️ . This repo isn't large enough to really need multiple jobs.