Narrow, non-authoritative, TTL-bound pre-V-B-A signal for collision-prone / high-blast / long-V-B-A lanes (deep memory-mining, tech-debt-radar, multi-turn architectural V-B-A). Distinct from authoritative `[lane-claim]` (post-V-B-A). Triggers: Use this skill BEFORE broadcasting `[lane-intent] evaluating #N` to confirm scope-trigger qualifies — narrow scope, not blanket coverage. Do NOT auto-fire for short single-turn V-B-A where direct `[lane-claim]` after V-B-A suffices.