feat: say which kinds of typescript diagnostic to report

[alexander-akait]

Summary

ignoreDiagnostics drops what a program answered; diagnosticOptions asks it for less, so a check that only wants syntax errors does not pay for the type checking it then throws away. It takes syntactic, semantic, declaration and global, and every kind is reported unless you turn one off.

What the tsconfig.json itself is wrong about is reported whatever is turned off — with the config file misread, nothing below it would be answering the right question — and build reports the whole of what it finds either way, since a solution is built rather than asked kind by kind.

Checked against the ecosystem first, as asked. fork-ts-checker-webpack-plugin is the only other plugin with this, so the option is spelled exactly as it spells it; its default is semantic alone, ours is everything, which is the behaviour this repo already had. vite-plugin-checker has nothing of the sort: its only filter is dev.logLevel: ('error' | 'warning')[] per checker, which is reportAs here and already shared across every check. Nothing new was invented.

Rebased onto main now that #339 has landed, so this is one commit again. #341 sits on top of it.

What kind of change does this PR introduce?

feat

Did you add tests for your changes?

Yes — test/typescript/kinds.test.js over a fixture holding one syntax error and one type error: every kind by default, each of the two turned off on its own, nothing reported with all four off, and a config file's own error reported even then.

Does this PR introduce a breaking change?

No — a new option, and nothing is turned off by default.

If relevant, what needs to be documented once your changes are merged or what have you already documented?

Documented in README.md under the TypeScript check, and the fork-ts-checker-webpack-plugin migration row updated.

Use of AI

Claude Code read vite-plugin-checker@0.14.5 and fork-ts-checker-webpack-plugin@9.1.0 for the option's shape, wrote the change, the tests and this description; I reviewed all of it.

🤖 Generated with Claude Code

https://claude.ai/code/session_01GzZci4NQeiqwdrVfd7dGXy