refactor: merge cycle policy into semantic validation layer

Wire SemanticValidator into the production validator pipeline and
consolidate cycle-policy types under core:validation.

- Add SemanticValidator(CycleExitRule(requirePolicyForCycles=false))
  to the prod ValidationPipeline (no-op default, preserves behavior)
- Move CyclePolicy/Binding/Signature/Factory from core:transitions.policy
  to core:validation.policy (validation already owns ValidationContext)
- Rename CyclePolicyBindingRule -> CycleExitRule (issue code unchanged)
- Delete dead CyclePolicyResolver + PolicyValidation

core/transitions/src/main/kotlin/com/correx/core/transitions/policy/CyclePolicyResolver.kt

@@ -1,12 +0,0 @@
-package com.correx.core.transitions.policy
-
-class CyclePolicyResolver(
-    private val bindings: Set<CyclePolicyBinding>
-) {
-
-    fun resolve(signature: CycleSignature): CyclePolicy? {
-        return bindings
-            .firstOrNull { it.cycle == signature }
-            ?.policy
-    }
-}

core/transitions/src/main/kotlin/com/correx/core/transitions/policy/PolicyValidation.kt

@@ -1,23 +0,0 @@
-package com.correx.core.transitions.policy
-
-class PolicyValidation {
-    fun validate(
-        bindings: Set<CyclePolicyBinding>,
-        knownCycles: Set<CycleSignature>
-    ): List<String> {
-
-        val errors = mutableListOf<String>()
-
-        val bound = bindings.map { it.cycle }.toSet()
-
-        val unbound = knownCycles - bound
-
-        if (unbound.isNotEmpty()) {
-            errors += unbound.map {
-                "Cycle $it has no policy binding"
-            }
-        }
-
-        return errors
-    }
-}

core/validation/src/main/kotlin/com/correx/core/validation/model/ValidationContext.kt

@@ -3,7 +3,7 @@ package com.correx.core.validation.model
 import com.correx.core.sessions.SessionState
 import com.correx.core.transitions.analysis.DetectedCycle
 import com.correx.core.transitions.graph.WorkflowGraph
-import com.correx.core.transitions.policy.CyclePolicyBinding
+import com.correx.core.validation.policy.CyclePolicyBinding
 
 data class ValidationContext(
     val graph: WorkflowGraph,

core/validation/src/main/kotlin/com/correx/core/validation/policy/CyclePolicy.kt

@@ -1,4 +1,4 @@
-package com.correx.core.transitions.policy
+package com.correx.core.validation.policy
 
 sealed interface CyclePolicy {
     data class Retry(

core/validation/src/main/kotlin/com/correx/core/validation/policy/CyclePolicyBinding.kt

@@ -1,4 +1,4 @@
-package com.correx.core.transitions.policy
+package com.correx.core.validation.policy
 
 data class CyclePolicyBinding(
     val cycle: CycleSignature,

core/validation/src/main/kotlin/com/correx/core/validation/policy/CycleSignature.kt

@@ -1,4 +1,4 @@
-package com.correx.core.transitions.policy
+package com.correx.core.validation.policy
 
 import com.correx.core.events.types.StageId
 import java.util.*

core/validation/src/main/kotlin/com/correx/core/validation/policy/CycleSignatureFactory.kt

@@ -1,4 +1,4 @@
-package com.correx.core.transitions.policy
+package com.correx.core.validation.policy
 
 import com.correx.core.events.types.StageId
 import com.correx.core.transitions.graph.TransitionEdge

core/validation/src/main/kotlin/com/correx/core/validation/semantic/rules/CycleExitRule.kt

@@ -1,12 +1,12 @@
 package com.correx.core.validation.semantic.rules
 
-import com.correx.core.transitions.policy.CycleSignatureFactory
+import com.correx.core.validation.policy.CycleSignatureFactory
 import com.correx.core.validation.model.ValidationContext
 import com.correx.core.validation.model.ValidationIssue
 import com.correx.core.validation.model.ValidationSeverity
 import com.correx.core.validation.semantic.SemanticRule
 
-class CyclePolicyBindingRule(
+class CycleExitRule(
     private val requirePolicyForCycles: Boolean
 ) : SemanticRule {