[4031434683] Upstream Reporter: Lalatendu Mohanty
Upstream issue status: Open
Upstream description:

With #119, #120, and #121 resolved, base-containers images will pre-configure index URLs so that consumers use plain version pins in pyproject.toml. Document this pattern so consumers know what to do and what to avoid.

*What to document:*

• Which env vars the base images set (`UV_EXTRA_INDEX_URL`, `UV_INDEX_URL`, `PIP_INDEX_URL`)
• How downstream overrides them via `--build-arg` to point at AIPCC
• Why plain `torch==X.Y.Z` resolves to CUDA wheels in both contexts (PyTorch index in midstream, AIPCC in downstream)
• What consumers must avoid putting in pyproject.toml:
• No `[[tool.uv.index]]` blocks for accelerator indexes
• No `+cu128` / `+rocm` local version suffixes
• No `[and-cuda]` extras
• No direct wheel URLs

Parent: #77