Replace SmootherTake macros with type-safe functions

[julianlitz]

Summary

This PR replaces the macros with inline functions to improve type safety and code maintainability without sacrificing performance. This is part of the broader effort to eliminate macro usage throughout GMGPolar.

Motivation

As discussed in #149, macros are error-prone and bypass C++'s type system, making bugs harder to catch at compile time. Macros in GMGPolar are currently used for code inlining, but modern C++ compilers handle inline functions just as efficiently in release builds while providing:

• Type safety: Compile-time type checking prevents misuse
• Better debugging: Functions appear in debuggers and stack traces
• Scope safety: No unintended name collisions or side effects

Merge Request - GuideLine Checklist

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• Tests for new functionality has been added
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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.11%. Comparing base (eaf5d34) to head (f6f47cf).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #163      +/-   ##
==========================================
+ Coverage   89.41%   90.11%   +0.70%     
==========================================
  Files          91       91              
  Lines        5241     5614     +373     
==========================================
+ Hits         4686     5059     +373     
  Misses        555      555              

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[EmilyBourne]

Looks good to me. Did you check if the timings were affected to see if we need to increase --param max-inline-insns-single further?

[julianlitz]

@Emily I can't really look into the benchmarks further, since my laptop is just not powerful and reliable enough. The timings looked fine, though I can't say for sure.

We could check later whether changing this instructions number impacts the runtime performance.