chore(experiments): add missing journals/ and results/ directories

[lornecodes]

Summary

• Creates journals/ directories (with .gitkeep) for 22 experiments that were missing them (score 4→5 upgrade)
• Creates both journals/ and results/ directories for 3 experiments: hodge_conjecture, pac_confluence_xi, symbolic_entropy_collapse (score 3→5 upgrade)
• Total: 28 new .gitkeep files across 25 experiments
• Container experiments (biology_experiments, entropy_information_polarity_field, pac_foundations_validation, quantum_validation) intentionally excluded — score 2 is expected for containers

Test plan

• Verify 22 experiments now have journals/ directory
• Verify hodge_conjecture, pac_confluence_xi, symbolic_entropy_collapse each have both journals/ and results/
• Confirm no container experiment directories were modified