release: 3.0.0

[dkulyk]

Prepare stable 3.0.0 after the reviewed API, transport and documentation changes. Merge baseline includes TypeScript 6.0.3 and ts-jest 29.4.14 while retaining Node 22 types.

Update package/lockfile versions, installation instructions, API reference, capability label and security version policy. Replace the unreleased adapter-final-chunk note with the stable contract and provide a stable changelog summary linking the breaking migration from 2.x. Preserve historical prerelease notes and measured performance snapshots.

Validation:

• Reproducible npm ci, build, Biome and packed type-resolution checks pass; 519 tests pass on Node and actual Bun.
• Smoke and all five differential verifiers pass on Node/Bun/Deno.
• Live OpenAI Structured Outputs/tool-call field streaming, cancellation and token-limit spike passed; captured output replay passes another 75 runtime/case combinations without new API calls.
• Fresh installed release archive passes ESM/CJS/Bun smoke, copying/boundary checks and strict TS 6 NodeNext/legacy CommonJS fixtures with Node 22 types.
• Nine README/guide examples run; local documentation links and packaged public pages checked.
• npm publish dry-run passes with explicit latest tag and public access.

No stable tag, GitHub release or npm publication has been performed. Publishing 3.0.0 with latest will replace 2.0.1 as the default installation; the existing beta tag remains separate.

All remote CI/CodeQL checks pass on final commit 623f402 (Node 22/24, Bun, Deno; both CodeQL languages).

Includes merged #64 (@types/node 22.20.5). Rebuilt archive is byte-identical to the previously installed and validated artifact.