Merge pull request #1939 from giuseppe/add-AGENTS.md

AGENTS.md: new file

Author: giuseppe

AGENTS.md

@@ -0,0 +1,31 @@
+# AGENTS.md
+
+## Code Style
+
+- Always preserve existing indentation style in each file, and validate it with
+  `make clang-format`.
+- Do not add inline comments explaining the change they belong to.
+
+## Git Commit Rules
+
+- Each logical change must be in its own separate commit.
+- Fixes for existing commits in the current branch must use fixup commits:
+  ```bash
+  git commit --fixup=<original-commit-hash>
+  ```
+
+## Commit Authorship
+
+- Keep the original author (do not change git config)
+- Add agent signature at the end of commit messages.
+
+## Adding New Files
+
+- New source or test files must be added to `Makefile.am`
+- After adding files, verify the build with `make distcheck`
+
+## Adding New Tests
+
+- Python tests go in `tests/test_*.py`, register in `all_tests` dict, and add to `PYTHON_TESTS` in root `Makefile.am`
+- C unit tests go in `tests/tests_libcrun_*.c`, add to `UNIT_TESTS` in root `Makefile.am` with build rules
+- Test functions should return `0` (pass), `-1` (fail), or `77` (skip)