Improve OData describe output

[wilsonfreitas]

Summary

• Make API-level describe() print detailed output for all OData endpoints by default
• Add describe(full=False) for the previous short endpoint listing
• Preserve describe("Endpoint") for a single endpoint and document the behavior

Closes #5

Tests

• uv run pytest tests/test_odata.py
• uv run ruff check bcb tests
• uv run mypy bcb
• uv run pytest
• uv run --group docs sphinx-build -b html docs docs/_build/html

Note: uv run ruff check still reports pre-existing notebook issues outside this change.