refactor(pkg): inline [Diagnostics] (#11322) #29608

Job	Run time
Nix (macos-latest)	1m 53s
Nix (ubuntu-latest)	54s
Documentation	54s
Build (macos-latest, 5.1.x)	12m 24s
Build (ubuntu-latest, 5.1.x)	8m 25s
Build (ocaml-variants.5.4.0+trunk, ubuntu-latest, true)	1m 28s
Format	1m 5s
Build (4.14.x, ubuntu-latest, true)	1m 29s
Coq 8.16.1	7m 8s
Build (4.14.x, macos-latest, true)	2m 58s
Wasm_of_ocaml	10m 33s
Build (5.1.x, macos-13, true)	3m 38s
Build monorepo benchmark docker image	3m 57s
Build (ocaml-base-compiler.4.14.2,system-msvc, windows-latest)	15m 33s
Build (ocaml-base-compiler.5.1.1,system-mingw, windows-latest)	8m 12s
Build (4.08.x, ubuntu-latest, true)	1m 26s
Build microbenchmarks	2m 31s
Create local opam switch (macos-latest, 5)	5m 17s
Create local opam switch (macos-latest, 4.14)	6m 1s
Build (4.04.x, ubuntu-latest, true, true)	5m 33s
Build (4.02.x, ubuntu-latest, true)	3m 48s
Create local opam switch (ubuntu-latest, 5)	4m 51s
Create local opam switch (ubuntu-latest, 4.14)	5m 10s
	1h 55m 8s

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