Recommend stdlib functions over Belt for converting between float/int/string #6698

Job	Run time
build-compiler (ubuntu-24.04, ocaml-variants.5.3.0+options,ocaml-option-static, true, true, linux...	1m 34s
build-rewatch (macos-13, x86_64-apple-darwin, darwin-x64)	16s
build-compiler (ubuntu-24.04-arm, ocaml-variants.5.3.0+options,ocaml-option-static, true, true, t...	13m 37s
build-rewatch (macos-14, aarch64-apple-darwin, darwin-arm64)	13s
build-compiler (macos-13, 5.3.0, true, darwin-x64)	26m 30s
build-rewatch (ubuntu-24.04, x86_64-unknown-linux-musl, linux-x64)	7s
build-compiler (macos-14, 5.3.0, true, darwin-arm64)	3m 20s
build-rewatch (ubuntu-24.04-arm, aarch64-unknown-linux-musl, linux-arm64)	24s
build-compiler (windows-latest, 5.3.0, true, win32-x64)	14m 53s
build-rewatch (windows-latest, x86_64-pc-windows-gnu, win32-x64)	33s
build-compiler (ubuntu-24.04, ocaml-variants.5.2.1+options,ocaml-option-static)	1m 53s
build-compiler (ubuntu-24.04, ocaml-variants.5.0.0+options,ocaml-option-static)	2m 12s
build-compiler (ubuntu-24.04, ocaml-variants.4.14.2+options,ocaml-option-static)	1m 48s
pkg-pr-new	0s
installationTest	0s
publish	0s
	1h 7m 20s

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