Add @types/node, update Python project URLs, and add CHANGELOG

[GsCommand]

Motivation

• Ensure TypeScript build does not rely on accidental transitive Node types by adding an explicit Node types dev dependency.
• Make the Python package metadata appear complete on PyPI by providing Homepage, Repository, Documentation, and Changelog links.
• Provide a minimal, honest CHANGELOG.md and link it from the repo README to improve release optics.

Description

• Added @types/node under devDependencies in typescript-sdk/package.json as "@types/node": "^20.17.0" to pin Node typings for the TypeScript SDK.
• Replaced the prior Python URL block in python-sdk/pyproject.toml with repository-based links for Homepage, Repository, Documentation, and Changelog.
• Added CHANGELOG.md at the repo root with a minimal 1.1.0 entry and linked it from README.md.
• Limited changes to metadata and docs only, preserving TypeScript strictness and not refactoring any unrelated code.

Testing

• Attempted a clean TypeScript validation run by removing node_modules/package-lock.json and running npm install, npm run typecheck, npm run build, and npm test, but npm install failed due to the environment's package proxy returning 403 Forbidden, so the full TS validation could not be completed.
• Verified the @types/node declaration by reading typescript-sdk/package.json and confirming devDependencies['@types/node'] is present.
• Attempted Python packaging validation with python -m build and twine check dist/*, but python -m build failed because the build tooling is not installed and pip install build twine is blocked by the same proxy 403 Forbidden, so artifact checks could not be run.
• Verified the edited metadata and wiring by inspecting python-sdk/pyproject.toml, README.md, and the newly created CHANGELOG.md, confirming the requested URLs and README link are present.

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Codex Task