docs: add pre-PR workflow and test failure documentation

- Add mandatory pre-PR checklist with linting and testing steps
- Document JVM restart error in test_sync_ontology.py
- Record PR #216 incident as learning example
- Emphasize importance of running tests before creating PRs

Author: Demirrr

.copilot/repo-memory.md

@@ -39,3 +39,55 @@ conda activate temp_owlapy && PYTHONPATH=. pytest --ignore=tests/test_z_do_last_
 conda activate temp_owlapy && coverage run -m pytest --ignore=tests/test_z_do_last_ebr_retrieval.py -p no:warnings -x
 conda activate temp_owlapy && coverage report -m
 ```
+
+## Pull Request Workflow
+
+**CRITICAL: Always run tests BEFORE creating a pull request!**
+
+### Pre-PR Checklist
+1. ✅ Run linter and fix issues:
+   ```bash
+   ruff check owlapy --line-length=200 --fix --unsafe-fixes
+   ```
+
+2. ✅ Run full test suite (excluding EBR):
+   ```bash
+   PYTHONPATH=. pytest --ignore=tests/test_z_do_last_ebr_retrieval.py -p no:warnings -x
+   ```
+
+3. ✅ Verify no test failures (especially JVM-related tests)
+
+4. ✅ Commit changes with descriptive message
+
+5. ✅ Push to feature branch
+
+6. ✅ Create pull request
+
+### Known Test Issues
+
+**JVM Restart Error in test_sync_ontology.py**
+- **Error**: `OSError: JVM cannot be restarted` in `test__eq__`
+- **Cause**: JPype cannot restart JVM within same Python process after stopJVM() is called
+- **Location**: `tests/test_sync_ontology.py::TestSyncOntology::test__eq__`
+- **Status**: Pre-existing issue, not introduced by documentation changes
+- **Impact**: Fails in CI when test runs after other JVM-dependent tests
+- **Workaround**: Run this test in isolation or fix test isolation issues
+
+**Always verify tests pass locally before creating PR to avoid CI failures.**
+
+## Recent Issues and Learnings
+
+### PR #216: Agent Documentation Fixes (May 2026)
+- **What happened**: Created PR without running tests first
+- **Result**: CI failed with JVM restart error in test_sync_ontology.py
+- **Lesson**: ALWAYS run `pytest tests -x` before creating PR
+- **Context**: The JVM restart error is a pre-existing issue unrelated to documentation changes, but it highlighted the importance of running tests before PR creation
+- **Fix needed**: Test isolation issue where `test__eq__` creates a new SyncOntology after JVM was stopped by previous tests
+
+### How to Detect Test Issues Before PR
+```bash
+# Run these commands in sequence before any PR:
+ruff check owlapy --line-length=200 --fix --unsafe-fixes  # Fix linting
+PYTHONPATH=. pytest --ignore=tests/test_z_do_last_ebr_retrieval.py -p no:warnings -x  # Run tests
+# Only create PR if both succeed
+```