Interpreter fixes: lvalue assignment and JFFI warnings

.gitignore

@@ -69,6 +69,7 @@ dev/prompts/CONTROL_FLOW_FIX_INSTRUCTIONS.md
 !README.md
 !QUICKSTART.md
 !CONTRIBUTING.md
+!AGENTS.md
 test_*.log
 test_*.json
 

AGENTS.md

@@ -0,0 +1,63 @@
+# PerlOnJava Agent Guidelines
+
+## Project Rules
+
+### Progress Tracking for Multi-Phase Work
+
+When working on multi-phase projects (like the Shared AST Transformer), **always update the design document when completing a phase**:
+
+1. **Mark the phase as completed** with date
+2. **Document what was done** (files changed, key decisions)
+3. **Update "Next Steps"** section so the user knows where to resume
+4. **Note any blockers or open questions**
+
+Example format at the end of a design doc:
+
+```markdown
+## Progress Tracking
+
+### Current Status: Phase 2 in progress
+
+### Completed Phases
+- [x] Phase 1: Infrastructure (2024-03-09)
+  - Created ASTAnnotation class
+  - Added typed fields to AbstractNode
+  - Files: AbstractNode.java, ASTAnnotation.java
+
+### Next Steps
+1. Implement VariableResolver visitor
+2. Add closure capture detection
+3. Run differential tests
+
+### Open Questions
+- Should we cache lvalue analysis results?
+```
+
+### Design Documents
+
+- Design documents live in `dev/design/`
+- Each major feature should have its own design doc
+- Keep docs updated as implementation progresses
+- Reference related docs and skills at the end
+
+### Testing
+
+- Run `./gradlew test` before committing
+- For interpreter changes, test with both backends:
+  ```bash
+  java -jar target/perlonjava.jar -e 'code'           # JVM backend
+  java -jar target/perlonjava.jar --int -e 'code'     # Interpreter
+  ```
+
+### Commits
+
+- Reference the design doc or issue in commit messages when relevant
+- Use conventional commit format when possible
+
+## Available Skills
+
+See `.cognition/skills/` for specialized debugging and development skills:
+- `debug-perlonjava` - General debugging
+- `interpreter-parity` - JVM vs interpreter parity issues
+- `debug-exiftool` - ExifTool test debugging
+- `profile-perlonjava` - Performance profiling