chore: add pre-commit configuration and CI

[nearlyforget]

Description:
This PR introduces automated code quality and formatting checks to the
JavaScript/TypeScript SDK. By using pre-commit, we ensure that all
contributions adhere to a consistent style before they are merged.

Tools & Hooks Added:

• Prettier: Formats TypeScript source files, JSON configurations, and
  GitHub Action workflows.
• ShellCheck: Lints generate_models.sh to prevent common shell
  scripting errors and ensure portability.
• codespell: Automatically detects and flags typos in source code and
  documentation.
• Hygiene Hooks: Standardizes end-of-file newlines and removes trailing
  whitespace.

CI/CD Integration:

• GitHub Actions (linter.yml): Runs the full suite of checks on every
  push and pull request to the main branch to prevent regressions