chore: replace Biome with oxlint, oxfmt and Knip

[Thomasims]

Replaces Biome with the shared @antelopejs/tooling-configs presets: oxlint
(type-aware, with the vendored anti-slop rules), oxfmt for formatting and Knip
for dead-code detection. oxlint is pinned to 1.81.0 because the JS plugin API
is still alpha and has to match the version tooling-configs builds against.

tsconfig

Type-aware linting runs through tsgolint, which rejects options TypeScript 7
removed, so moduleResolution: "node" and baseUrl are gone and the
self-referential @antelopejs/interface-api path mapping the test suite uses is
now written relative (./src/index.ts), which is what the compiler wants once
baseUrl is absent.

module stays commonjs on purpose. Raising it to node16 would look like the
tidier fix and is a runtime break: tsc stops downlevelling dynamic imports and
emits native ESM ones, which bypass the CommonJS resolver detour the ajs
runtime installs. The emit was checked to still go through require.

pnpm build succeeds with no source change.

Code changes the linter forced

Only import ordering, all applied by oxlint --fix
(perfectionist(sort-imports)) in src/index.ts and the two test suites.
Nothing was disabled, and no public export was touched: this package is a
versioned contract, so its surface is deliberately unchanged.

The remaining oxlint output is warnings only (max-lines, max-params,
unbound-method, anti-slop(no-chained-type-assertions)), which are a
deliberate backlog and are left as they are. pnpm lint exits 0.

Knip

The suites live in src/tests/ and src/antelope.test.ts is read by
ajs module test from package.json#antelopeJs.test; the preset only knows the
src/test/ spelling, so both are declared as entry points. Without that, Knip
reads the whole suite as dead code and then sinon, ws and their types as
unused. ajs itself is ignored as a binary because CI installs
@antelopejs/core globally instead of adding the CLI to every package.

Nothing was deleted. Knip reports no unused files, exports or dependencies.

Verification

pnpm build, pnpm lint, pnpm knip, pnpm format:check all exit 0.
pnpm test: 83 passing, identical to the baseline measured on an untouched
main worktree.

The oxfmt pass is a separate commit and is recorded in .git-blame-ignore-revs
so git blame stays readable. It also normalizes Markdown, YAML and the
package.json key order, which accounts for most of the diff.