Move the behavior adjustment tool, rules prompt, merge templates, and DOX into a _behavior_adjustment plugin so durable behavior, personality, style, and response-format rules ship as a standard plugin. Rules persist in the memory subdirectory, the system-prompt extension injects them at the front, and normalization keeps merged rulesets deduplicated. The tool prompt drops the stale promptinclude guidance that no longer matches how the tool writes rules. The tool logs its message as its own `behavior_adjustment` type with an `icon://psychology Adjusting behavior` headline rendered through a BEH badge handler in the brain pink accent.
Validation: pytest tests/test_tool_action_contracts.py tests/test_responses_tools.py tests/test_behavior_tool_ui.py
