Fix QTT API compatibility and deuteron documentation build

[ohno]

Fixes the failures in CI run 37355989088.

• Qualify TwoBody.Laplacian in the Minnesota deuteron example, since it is not exported.
• Update QTT cross interpolation, compression, and DMRG keyword arguments to the TensorTrainNumerics 1.1.6 API, and disable its progress output explicitly.
• Raise the minimum TensorTrainNumerics version to 1.1.6 to match the API used by the extension.

Validation in PR CI:

• Core installation without optional dependencies: passed.
• Julia 1.10: all 888 tests passed, including all 82 QTT tests; coverage upload passed.
• Julia 1.12 and documentation/doctests: still running at the time of this update.

The API mappings were also checked against the upstream v1.1.6 source. Julia is unavailable in the editing environment, so execution validation uses GitHub Actions.

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This pull request was developed with assistance from Codex using GPT-6 Astra with High reasoning effort.

[codecov]

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