A peer of ContradictionAgent. Subscribes to the same raw evidence stream (branch_evidence_<session>) and runs strictly weaker unification than CA — pair-level only — turning σs into per-recipe instantiation hints.

Gated behind params.suggestions_enabled (default false). When disabled, init/1 returns immediately without subscribing to the topic and no message handling runs, so the prover's behaviour is unchanged.

Current state (Step 3 of the SuggestionAgent plan)

This is the stub stage: SA logs suggestions but does not publish. The :suggestions ETS table and the worker splice points land in Step 4.