chore: bring working tree to HEAD — gitignore + CLAUDE.md + fixtures

- .gitignore: extended with noise (.DS_Store, *.log, .aw/, *.db, *.bak,
  sailo-claude-backup/, superpowers/, agents/, scripts/, foreign docs)
- CLAUDE.md: project-specific config (was untracked)
- pluxee-todo.md + pluxee-todo.pdf: fixtures and sample output

.gitignore

@@ -28,3 +28,9 @@ vectors.db
 # Generated test artifacts
 tests/_tmp_*.docx
 tests/_tmp_*.pdf
+
+# Foreign trees copied from other projects — do NOT commit
+superpowers/
+agents/
+scripts/
+docs/ARCHITECTURE_PROPOSAL.md