CI: Add formatting validation steps

[jserv]

The following scripts are added to GitHub Actions workflow:

• check-format.sh to validate C/C++ and shell script formatting
• check-newline.sh to ensure files end with newline

Close #33

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Summary by cubic

Adds formatting and newline checks to CI to enforce a consistent code style and fail fast on mismatches. Also reformats CI shell scripts for consistent style; no logic changes.

• New Features

  • Added .ci/check-format.sh (clang-format-18 for C/C++, shfmt for shell).
  • Added .ci/check-newline.sh to ensure tracked text files end with a newline (skips binaries).
  • Integrated both checks into .github/workflows/ci.yml.
  • Added .editorconfig to standardize shell script formatting.

• Dependencies

  • Installs clang-format-18 and shfmt in CI.

^{Written for commit d57e45a. Summary will update automatically on new commits.}

[github-actions]

Linmo CI Test Results

Overall Status: ✅ passed
Timestamp: 2025-11-19T19:06:54+00:00

Toolchain Results

Toolchain	Build	Crash Test	Functional
GNU	✅ passed	✅ passed	✅ passed
LLVM	✅ passed	⏭️ skipped	⏭️ skipped

Application Tests

App	GNU	LLVM
cond	✅ passed	⏭️ skipped
coop	✅ passed	⏭️ skipped
cpubench	✅ passed	⏭️ skipped
echo	✅ passed	⏭️ skipped
hello	✅ passed	⏭️ skipped
mqueues	✅ passed	⏭️ skipped
mutex	✅ passed	⏭️ skipped
pipes	✅ passed	⏭️ skipped
pipes_small	✅ passed	⏭️ skipped
pipes_struct	✅ passed	⏭️ skipped
prodcons	✅ passed	⏭️ skipped
progress	✅ passed	⏭️ skipped
rtsched	✅ passed	⏭️ skipped
semaphore	✅ passed	⏭️ skipped
suspend	✅ passed	⏭️ skipped
test64	✅ passed	⏭️ skipped
test_libc	✅ passed	⏭️ skipped
timer	✅ passed	⏭️ skipped
timer_kill	✅ passed	⏭️ skipped

Functional Test Details

Test	GNU	LLVM
mutex:data_consistency	✅ passed	⏭️ skipped
mutex:fairness	✅ passed	⏭️ skipped
mutex:mutual_exclusion	✅ passed	⏭️ skipped
mutex:overall	✅ passed	⏭️ skipped
semaphore:all_tests_passed!	✅ passed	⏭️ skipped

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Report generated from test-summary.toml

[cubic-dev-ai]

No issues found across 8 files