Add open-batch-llm CLI project with uv build system and PyPI CI

[Copilot]

Bootstraps open-batch-llm as a publishable Python CLI package using uv + hatchling, with GitHub Actions CI for testing and automated PyPI publishing.

Package structure

• src/open_batch_llm/ — src-layout package with __version__ = "0.1.0"
• pyproject.toml — hatchling build backend, runtime deps (click, httpx, rich), open-batch-llm entry point, dev group with pytest
• uv.lock — pinned lockfile

CLI (open-batch-llm)

Two subcommands operating on a JSON array of {"id", "prompt"} objects:

# Validate input structure without calling any API
open-batch-llm validate requests.json

# Dry-run or submit batch requests
open-batch-llm run requests.json --provider anthropic --model claude-3-haiku --output results.json
open-batch-llm run --dry-run requests.json

CI/CD

• ci.yml — test matrix across Python 3.10/3.11/3.12 on every push/PR to main
• publish.yml — triggered on GitHub Release; builds wheel + sdist then publishes via Trusted Publishing (OIDC) — no stored API token required. Requires a matching PyPI Trusted Publisher entry configured for this repo and workflow file.

Original prompt

create a simple cli python project 'open-batch-llm' using uv as package manager and build system. Add ci to upload the project to PyPi