docs: add SAFETY comments for StrStack unsafe blocks #2

	name: ci

	on:
	push:
	pull_request:

	jobs:
	policy:
	name: policy (no Cargo.lock)
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	- name: Fail if Cargo.lock is committed
	run: \|
	set -euo pipefail
	if git ls-files \| grep -Eq '(^\|/)Cargo\.lock$'; then
	echo "error: Cargo.lock must not be committed in library repositories (it should be gitignored)." >&2
	exit 1
	fi

	fmt:
	name: fmt
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	- uses: dtolnay/rust-toolchain@nightly
	with:
	components: rustfmt
	- name: cargo fmt (check)
	run: cargo +nightly fmt --all -- --check

	test:
	name: check / test / clippy
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	- uses: dtolnay/rust-toolchain@stable
	with:
	components: clippy
	- name: cargo check
	run: cargo check --all-targets
	- name: cargo test
	run: cargo test
	- name: cargo clippy
	run: cargo clippy --all-targets -- -D warnings

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