fix(formulas): remove duplicate review_id var in idea-to-plan formula

Duplicate [vars.review_id] block caused TOML parse error at line 423.

Author: olpie101

internal/formula/formulas/mol-idea-to-plan.formula.toml

@@ -419,8 +419,3 @@ required = true
 description = "Additional context: constraints, related code, prior decisions, linked beads"
 required = false
 default = ""
-
-[vars.review_id]
-description = "Short slug for this review, generated by the intake step (e.g. notification-levels)"
-required = false
-default = ""