Integrate on boundary to compute length scale quantities

[unalmis]

This pull request is waiting on #1127 .

See #1101, in particular this comment for some of other changes.

Some quantities like the plasma volume V, major radius R0, minor radius a etc. can be computed via stoke's theorem on the last closed flux surface. This pull request modifies the compute functions to default to such an integration on the boundary rather than throughout the volume so that the length scale quantities can be computed accurately on grids other than QuadratureGrid. This lets us avoid building transforms for QuadratureGrid in objectives, saving memory.

Also, might have some improvements in general

1. Reducing dimensionality of integral makes integration more tractable with faster convergence.
2. Transforming the integration to one over periodic domains makes it more accurate due to the exponential convergence of the quadrature on periodic domains.

[github-actions]

|             benchmark_name             |         dt(%)          |         dt(s)          |        t_new(s)        |        t_old(s)        | 
| -------------------------------------- | ---------------------- | ---------------------- | ---------------------- | ---------------------- |
 test_build_transform_fft_lowres         |     -0.82 +/- 3.54     | -4.55e-03 +/- 1.96e-02 |  5.49e-01 +/- 1.2e-02  |  5.54e-01 +/- 1.5e-02  |
 test_equilibrium_init_medres            |     +0.06 +/- 1.38     | +2.47e-03 +/- 6.05e-02 |  4.39e+00 +/- 3.4e-02  |  4.39e+00 +/- 5.0e-02  |
 test_equilibrium_init_highres           |     +0.55 +/- 1.23     | +3.12e-02 +/- 6.97e-02 |  5.69e+00 +/- 5.9e-02  |  5.66e+00 +/- 3.8e-02  |
 test_objective_compile_dshape_current   |     +0.08 +/- 1.20     | +3.09e-03 +/- 4.80e-02 |  4.00e+00 +/- 4.0e-02  |  4.00e+00 +/- 2.7e-02  |
 test_objective_compute_dshape_current   |     +0.78 +/- 4.34     | +4.10e-05 +/- 2.29e-04 |  5.32e-03 +/- 1.3e-04  |  5.28e-03 +/- 1.9e-04  |
 test_objective_jac_dshape_current       |     +3.36 +/- 7.85     | +1.43e-03 +/- 3.35e-03 |  4.41e-02 +/- 3.1e-03  |  4.26e-02 +/- 1.3e-03  |
 test_perturb_2                          |     +0.03 +/- 1.78     | +6.59e-03 +/- 3.63e-01 |  2.04e+01 +/- 1.9e-01  |  2.04e+01 +/- 3.1e-01  |
 test_proximal_freeb_jac                 |     -0.17 +/- 0.95     | -1.27e-02 +/- 7.06e-02 |  7.42e+00 +/- 4.8e-02  |  7.43e+00 +/- 5.2e-02  |
 test_solve_fixed_iter                   |     +0.43 +/- 2.16     | +1.39e-01 +/- 7.07e-01 |  3.29e+01 +/- 3.7e-01  |  3.27e+01 +/- 6.0e-01  |
 test_LinearConstraintProjection_build   |     +0.29 +/- 2.57     | +3.04e-02 +/- 2.74e-01 |  1.07e+01 +/- 2.2e-01  |  1.06e+01 +/- 1.6e-01  |
 test_build_transform_fft_midres         |     +0.78 +/- 4.16     | +4.77e-03 +/- 2.56e-02 |  6.20e-01 +/- 2.1e-02  |  6.15e-01 +/- 1.5e-02  |
 test_build_transform_fft_highres        |     +0.41 +/- 1.93     | +3.97e-03 +/- 1.89e-02 |  9.84e-01 +/- 1.5e-02  |  9.80e-01 +/- 1.1e-02  |
 test_equilibrium_init_lowres            |     -0.10 +/- 1.73     | -3.99e-03 +/- 6.85e-02 |  3.94e+00 +/- 5.3e-02  |  3.95e+00 +/- 4.4e-02  |
 test_objective_compile_atf              |     -1.32 +/- 1.56     | -1.09e-01 +/- 1.29e-01 |  8.18e+00 +/- 1.2e-01  |  8.29e+00 +/- 4.7e-02  |
 test_objective_compute_atf              |     -0.35 +/- 4.75     | -5.71e-05 +/- 7.70e-04 |  1.62e-02 +/- 5.8e-04  |  1.62e-02 +/- 5.1e-04  |
 test_objective_jac_atf                  |     -1.89 +/- 2.14     | -3.83e-02 +/- 4.33e-02 |  1.98e+00 +/- 3.1e-02  |  2.02e+00 +/- 3.0e-02  |
 test_perturb_1                          |     -0.23 +/- 1.15     | -3.51e-02 +/- 1.73e-01 |  1.50e+01 +/- 9.4e-02  |  1.50e+01 +/- 1.5e-01  |
 test_proximal_jac_atf                   |     +0.61 +/- 0.70     | +5.08e-02 +/- 5.83e-02 |  8.37e+00 +/- 4.2e-02  |  8.32e+00 +/- 4.1e-02  |
 test_proximal_freeb_compute             |     -0.59 +/- 0.84     | -1.20e-03 +/- 1.70e-03 |  2.03e-01 +/- 1.0e-03  |  2.04e-01 +/- 1.3e-03  |
 test_solve_fixed_iter_compiled          |     -1.20 +/- 0.74     | -2.51e-01 +/- 1.55e-01 |  2.06e+01 +/- 1.3e-01  |  2.09e+01 +/- 8.2e-02  |

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