Add support for running multiple commands on a single “id”

[pygarap]

Add support for running multiple commands on a single “id” and support multiline in the “entry” field, something like this:

repos:
  - repo: local
    hooks:
      - id: test-all
        name: Run pytest across CPython 3.10–3.13 via uv
        language: system
        entry: |-
            uv run --python=3.10 --isolated pytest
            uv run --python=3.11 --isolated pytest
            uv run --python=3.12 --isolated pytest
            uv run --python=3.13 --isolated pytest

[ashb]

This works today:

repos:
  - repo: local
    hooks:
      - id: test-all
        name: Run pytest across CPython 3.10–3.13 via uv
        language: system
        entry: uv run --python=3.10 --isolated pytest
      - id: test-all
        language: system
        entry: uv run --python=3.11 --isolated pytest

Or use nox/tox for this