Remove check_memory() from lib/formula-session.sh and update all *-run.sh scripts
to use memory_guard() from lib/env.sh.
Changes:
- lib/formula-session.sh: Removed check_memory() function and its documentation
- gardener/gardener-run.sh: Replaced check_memory(2000) with memory_guard(2000)
- planner/planner-run.sh: Replaced check_memory(2000) with memory_guard(2000)
- architect/architect-run.sh: Replaced check_memory(2000) with memory_guard(2000)
- predictor/predictor-run.sh: Replaced check_memory(2000) with memory_guard(2000)
- supervisor/supervisor-run.sh: Replaced check_memory(2000) with memory_guard(2000)
Benefits:
- Only one memory check function exists now
- All agents use the same function
- No dependency on free command - uses /proc/meminfo which is more portable
