11bc3107

By: ValentinHirschi <valentin.hirschi@gmail.com>

normalize the integrated threshold radial profile

Use h(r/r_star)/r_star in the scalar and dual normalization owner. The
generated helper cancels the radial measure, so the previous inverted
argument integrated to an inverse-second moment instead of one. Default
power-zero, sigma-one profiles are mathematically unchanged. Add unit
radial-normalization and analytic first/second derivative regressions.

Validation: cargo fmt --all -- --check; cargo check --workspace --all-targets;
cargo nextest run -p gammalooprs --lib -E 'test(integrated_ct_profile)'
--retries 0 (2 passed); cargo clippy -p gammalooprs -p gammaloop-api
--all-targets --features ufo_support -- -D warnings. Independent reviews
verified the full single/mixed/amplitude radial measures and test oracles.

User request:
Continue as planned, but look into the current implementation, it should already offer such flexibility.
But feel free to add some if you need be (but make sure it's steered through runtime integrand toml parameters so the user can easily access it). And it's only weakly tested, so if you find any bug there you can also adjust it.