CI: consolidate workflows for source and docs check

A bunch of tiny jobs that run various source or documentation checks are
consolidated into two workflow files: checksrc.yml and checkdocs.yml.
This reduces the proliferation of new files containing one-line checks
and brings those that operate similarly together for better reasoning
about them. The man-examples check is also now running again for the
first time in 7 months.

Various calls to find, xargs and git ls-files are changed where possible
to use NUL line terminators in pipes to avoid issues with oddly-named
files that might find their way into the repo.

Closes #14654

.github/workflows/checksrc.yml

@@ -2,28 +2,93 @@
 #
 # SPDX-License-Identifier: curl
 
-name: checksrc
+# This workflow contains checks at the source code level only.
+
+name: Source
 
 on:
-  # Trigger the workflow on push or pull requests, but only for the
-  # master branch
   push:
     branches:
       - master
       - '*/ci'
+    paths-ignore:
+      - '**/*.md'
+      - '**/CMakeLists.txt'
+      - '.azure-pipelines.yml'
+      - '.circleci/**'
+      - 'appveyor.*'
+      - 'CMake/**'
+      - 'plan9/**'
+      - 'tests/data/**'
+      - 'winbuild/**'
   pull_request:
     branches:
       - master
+    paths-ignore:
+      - '**/*.md'
+      - '**/CMakeLists.txt'
+      - '.azure-pipelines.yml'
+      - '.circleci/**'
+      - 'appveyor.*'
+      - 'CMake/**'
+      - 'plan9/**'
+      - 'tests/data/**'
+      - 'winbuild/**'
 
 permissions: {}
 
 jobs:
-  all:
-
+  checksrc:
     runs-on: ubuntu-latest
-
     steps:
       - uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332 # v4
+        name: checkout
 
       - name: check
-        run: git ls-files "*.[ch]" | xargs -n1 ./scripts/checksrc.pl
+        run: git ls-files -z "*.[ch]" | xargs -0 -n1 ./scripts/checksrc.pl
+
+  codespell:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332 # v4
+        name: checkout
+
+      - name: install
+        run: |
+          sudo rm -f /etc/apt/sources.list.d/microsoft-prod.list
+          sudo apt-get update
+          sudo apt-get install codespell
+
+      - name: spellcheck
+        run: codespell --skip src/tool_hugehelp.c -I .github/scripts/codespell-ignore.txt include src lib
+
+  reuse:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332 # v4
+        name: checkout
+
+      - name: REUSE Compliance Check
+        uses: fsfe/reuse-action@3ae3c6bdf1257ab19397fab11fd3312144692083 # v4
+
+  miscchecks:
+    runs-on: ubuntu-latest
+    timeout-minutes: 5
+    steps:
+      - uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332 # v4
+        name: checkout
+
+      - name: shellcheck
+        run: .github/scripts/shellcheck.sh
+
+      - name: spacecheck
+        run: .github/scripts/spacecheck.pl
+
+      - name: binarycheck
+        run: .github/scripts/binarycheck.pl
+
+      # we allow some extra in source code
+      - name: badwords
+        run: >
+          grep -Ev '(\\bwill| url | dir )' .github/scripts/badwords.txt |
+          .github/scripts/badwords.pl `git ls-files -- src lib include`