- skills/fold-sast: rename to skill-fold-sast and expand the scan/precision
guidance for C++/Rust/Swift lanes
- docs/architecture: record call-graph phase decomposition and the
optimization-loop TP/FP/TN/FN evidence policy
- docs/mcp-tools + README: update budget/per-query defaults (1800s/6000ms)
and note the OpenGrep pre-push hook
