Adds clang-format, nixfmt, and shellcheck in CI. (#77)

Signed-off-by: Nathan Ringo <me@remexre.com>

Author: remexre

.devcontainer/Dockerfile

@@ -4,20 +4,23 @@
 
 FROM docker.io/alpine:3.21
 RUN apk add --no-interactive \
-            bash \
-            binutils-riscv-none-elf \
-            busybox-extras \
-            coreutils \
-            gcc-riscv-none-elf \
-            gdb-multiarch \
-            git \
-            make \
-            mdbook \
-            minicom \
-            openssh \
-            perl \
-            python3 \
-            qemu-system-riscv64 \
-            reuse \
-            tar \
-            zstd
+	bash \
+	binutils-riscv-none-elf \
+	busybox-extras \
+	clang-extra-tools \
+	coreutils \
+	gcc-riscv-none-elf \
+	gdb-multiarch \
+	git \
+	make \
+	mdbook \
+	minicom \
+	openssh \
+	perl \
+	python3 \
+	qemu-system-riscv64 \
+	reuse \
+	shellcheck \
+	tar \
+	tio \
+	zstd

.github/workflows/lint.yml

@@ -0,0 +1,37 @@
+# SPDX-FileCopyrightText: 2025 ukoOS Contributors
+#
+# SPDX-License-Identifier: GPL-3.0-or-later
+
+name: Linting
+on:
+  push:
+  pull_request:
+jobs:
+  lint:
+    runs-on: 'ubuntu-latest'
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+      - name: Install Nix
+        uses: cachix/install-nix-action@v31
+        with:
+          github_access_token: ${{ secrets.GITHUB_TOKEN }}
+      - name: Set up Cachix
+        uses: cachix/cachix-action@v14
+        with:
+          name: ukoos
+          authToken: ${{ secrets.CACHIX_AUTH_TOKEN }}
+      - name: Check REUSE
+        run: |
+          nix develop --command reuse lint
+      - name: Check formatting
+        run: |
+          nix fmt -- --ci
+          nix develop --command \
+            find -name '*.c' -or -name '*.h' \
+              -exec clang-format --dry-run -Werror -- {} +
+      - name: Lint configure script
+        run: |
+          # TODO: Any other shell scripts should end up here.
+          nix develop --command \
+            shellcheck configure

.github/workflows/reuse-lint.yml

@@ -90,11 +90,15 @@
           ];
           nativeBuildInputs = [
             pkgs.bear
+            pkgs.clang-tools
             pkgs.dtc
             pkgs.gdb
             pkgs.minicom
+            pkgs.nixfmt-rfc-style
             pkgs.qemu
             pkgs.reuse
+            pkgs.shellcheck
+            pkgs.tio
           ];
           shellHook = ''
             export CC=riscv64-none-elf-gcc
@@ -103,6 +107,8 @@
           '';
         };
 
+        formatter = pkgs.nixfmt-tree;
+
         packages = ukoos-packages // {
           default = packages."ukoos/milkv-duos";