force specialization in sv_ecef_to_ecef

[disberd]

I found out that I had unexpected allocations when using the SatelliteToolbox ecosystem and I pinpointed this down to the sv_ecef_to_ecef function.

This small PR tries to force specialization for this function as the generic args... can often lead to allocations due to lack of specialization (see this section of the performance tips)

A benchmark of the function before and after this PR on my linux machine gives the following improvement:

# Before this PR
BenchmarkTools.Trial: 10000 samples with 162 evaluations.
 Range (min … max):  656.858 ns … 39.471 μs  ┊ GC (min … max):  0.00% … 96.59%
 Time  (median):     687.685 ns              ┊ GC (median):     0.00%
 Time  (mean ± σ):   870.394 ns ±  2.221 μs  ┊ GC (mean ± σ):  15.98% ±  6.12%

  ▅██▇▅▄▄▃▃▃▃▃▃▂▂▁▂▁▁▁                                         ▂
  ███████████████████████▇▇█▇▆▇▅▆▆▆▅▃▅▄▄▄▅▅▅▆▆▆▆▄▆▆▆▇▆▇▅▇▇█▆▆▆ █
  657 ns        Histogram: log(frequency) by time      1.31 μs <

 Memory estimate: 1.11 KiB, allocs estimate: 15.

# After this PR
BenchmarkTools.Trial: 10000 samples with 900 evaluations.
 Range (min … max):  123.292 ns … 200.348 ns  ┊ GC (min … max): 0.00% … 0.00%
 Time  (median):     126.317 ns               ┊ GC (median):    0.00%
 Time  (mean ± σ):   127.951 ns ±   6.883 ns  ┊ GC (mean ± σ):  0.00% ± 0.00%

    ▄▆█▆                                                         
  ▆█████▅▃▃▃▃▃▃▃▃▃▃▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▁▂▂▂▂▂▂▂▂▂▂▂▂▂ ▃
  123 ns           Histogram: frequency by time          166 ns <

 Memory estimate: 0 bytes, allocs estimate: 0.

Test code (taken from package tests)

using SatelliteToolboxTransformations
using BenchmarkTools

eop_iau1980  = read_iers_eop("test/eop_IAU1980.txt",  Val(:IAU1980))

JD_UTC = date_to_jd(2004, 4, 6, 7, 51, 28.386009)

# ITRF => PEF
# ======================================================================================

r_itrf  = [-1033.4793830; 7901.2952754; 6380.3565958]
v_itrf  = [-3.225636520; -2.872451450; +5.531924446]
sv_itrf = OrbitStateVector(JD_UTC, r_itrf, v_itrf)
@benchmark sv_ecef_to_ecef($sv_itrf, ITRF(), PEF(), $JD_UTC, $eop_iau1980)

[codecov]

Codecov Report

Patch coverage: 100.00% and no project coverage change.

Comparison is base (4f24b33) 100.00% compared to head (4129ee7) 100.00%.

Additional details and impacted files

@@            Coverage Diff            @@
##              main        #2   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           30        30           
  Lines         1160      1160           
=========================================
  Hits          1160      1160           

Files Changed	Coverage Δ
src/orbit/sv_ecef_to_ecef.jl	100.00% <100.00%> (ø)

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[ronisbr]

Awesome! Thank you very much @disberd !