Restructure tests to all run in bazel

- add rules to run tests for a specific platform
- use downloaded buildifier
- move lint to a script
- rename ci tasks
- stop running under qemu-aarch64-static as it doesn't do anything

ci/lint

@@ -0,0 +1,9 @@
+#!/bin/bash
+set -euo pipefail
+
+REPO_ROOT=$(git rev-parse --show-toplevel)
+cd "$REPO_ROOT"
+
+# shellcheck disable=SC2046
+shellcheck -x $(awk '/#!\/bin\/(ba)?sh/&&FNR==1{print FILENAME}' $(git ls-files))
+find . \( -name 'WORKSPACE' -o -name 'BUILD' -o -name '*.bzl' \) -exec buildifier {} +

ci/test

@@ -1,34 +1,4 @@
 #!/bin/bash
 set -euo pipefail
 
-cd "$(dirname "$0")/.."
-. .envrc
-
-_run() {
-    >&2 echo
-    >&2 echo "  $*"
-    >&2 echo
-    "$@"
-}
-
-while read -r action platform toolchain config; do
-    args=("$@")
-    if [[ $config != : ]]; then
-        args+=(--config="$config")
-    fi
-
-    args+=(\
-        --platforms "@zig_sdk//platform:${platform}" \
-        --extra_toolchains "@zig_sdk//toolchain:${toolchain}" \
-        //test/... \
-    )
-
-    _run bazel "$action" "${args[@]}"
-
-done <<EOF
-test linux_amd64 linux_amd64_musl :
-test linux_amd64 linux_amd64_gnu.2.19 :
-test linux_arm64 linux_arm64_musl qemu-aarch64
-test linux_arm64 linux_arm64_gnu.2.28 qemu-aarch64
-build darwin_amd64 darwin_amd64 :
-EOF
+bazel test ...