Rewatch: preserve warnings after atomic-save full rebuilds #9903

Job	Run time
test-devcontainer	16m 43s
build-compiler (ubuntu-24.04, ocaml-variants.5.3.0+options,ocaml-option-static, true, true, linux...	5m 36s
build-compiler (windows-2025, 5.3.0, true, win32-x64, x86_64-pc-windows-gnu, .exe, release)	10m 12s
build-compiler (ubuntu-24.04, ocaml-variants.5.0.0+options,ocaml-option-static, linux-x64, x86_64...	4m 26s
build-compiler (macos-15, 5.3.0, true, darwin-arm64, aarch64-apple-darwin, release)	5m 28s
build-compiler (macos-15-intel, 5.3.0, true, darwin-x64, x86_64-apple-darwin, release)	10m 30s
build-compiler (ubuntu-24.04-arm, ocaml-variants.5.3.0+options,ocaml-option-static, true, true, t...	5m 12s
pkg-pr-new	51s
api-docs	2m 55s
test-installation-pnpm (macos-15)	18s
test-installation-pnpm (windows-2025)	1m 2s
test-installation-pnpm (macos-15-intel)	47s
test-installation-pnpm (ubuntu-24.04-arm)	22s
test-installation-pnpm (ubuntu-24.04)	21s
test-installation-npm (macos-15-intel)	51s
test-installation-npm (ubuntu-24.04)	13s
test-installation-npm (windows-2025)	44s
test-installation-npm (ubuntu-24.04-arm)	16s
test-installation-npm (macos-15)	15s
test-integration-rewatch (ubuntu-24.04)	3m 54s
test-integration-rewatch (macos-15-intel)	5m 53s
test-integration-rewatch (macos-15)	4m 28s
test-integration-rewatch (windows-2025)	7m 9s
test-integration-rewatch (ubuntu-24.04-arm)	2m 56s
publish	0s
	1h 31m 22s

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