chore: Bump version to 1.0.0 and update README with Pydantic v2 notice

[Martin005]

This pull request upgrades the phrasetms_client Python package to version 1.0.0, marking a major release. The update introduces compatibility with Pydantic v2 and updates version references throughout the codebase. It also includes a minor dependency import change.

Version upgrade and compatibility notice:

• Updated the package version to 1.0.0 across all relevant files: pyproject.toml, setup.py, phrasetms_client/__init__.py, and phrasetms_client/configuration.py. [1] [2] [3] [4] [5]
• Added a note in README.md to inform users that starting with version 1.0.0, the client uses Pydantic v2 and recommends staying on 0.x.x for Pydantic v1 compatibility.

Dependency update:

• Changed import from urllib3 to urllib3.util in phrasetms_client/configuration.py for improved dependency handling.