Module for reading grid from file

[ryanmrichard]

Is this pull request associated with an issue(s)?
No.

Description
This PR adds a module that can read a DFT quadrature grid from a file. The module ignores the input molecule and simply reads the grid, i.e., the module does NOT assert that the grid makes sense for the input molecule.

At present, this module is primarily intended as a workaround for not being able to easily get the final integration grid from GauXC. Down the road, it may prove useful for checking grid correctness or allowing people to brute-force use custom grids.

TODOs
None assuming it passes CI.

[Copilot]

Pull Request Overview

This PR adds a module for reading DFT quadrature grids from text files, intended as a workaround for grid extraction limitations in GauXC and potential future use for grid validation or custom grids.

• Implements GridFromFile module that reads grid points with coordinates and weights from space-separated text files
• Includes comprehensive unit tests covering file existence validation and grid parsing functionality
• Integrates the new module into the existing module loading infrastructure

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
src/scf/xc/grid_from_file.cpp	Main implementation of the GridFromFile module with file parsing logic
src/scf/xc/xc.hpp	Declares the GridFromFile module
src/scf/xc/xc.cpp	Registers the GridFromFile module in the module manager
tests/cxx/unit_tests/xc/grid_from_file.cpp	Unit tests for file reading and error handling

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[ryanmrichard]

r2g

[github-actions]

🚀 [bumpr] Bumped!
New version:v0.0.32
Changes:v0.0.31...v0.0.32