feat(personalization): OperatorProfileBoundEvent + bind-at-start + inject about context

Records operator profile as a snapshot event at session start (invariants #8/#9),
populates SessionState.boundProfile via reducer, and injects the about text as a
pinned L0 SYSTEM context entry in every stage. Gated by PersonalizationConfig.enabled.

core/kernel/src/main/kotlin/com/correx/core/kernel/orchestration/SessionOrchestrator.kt

@@ -333,8 +333,23 @@ abstract class SessionOrchestrator(
         )
         val repoMapEntries = buildRepoMapEntries(sessionId)
         val needsEntries = buildNeedsArtifactEntries(sessionId, stageConfig)
+        val profileEntries = session.state.boundProfile?.about
+            ?.takeIf { it.isNotBlank() }
+            ?.let { about ->
+                listOf(
+                    ContextEntry(
+                        id = ContextEntryId(UUID.randomUUID().toString()),
+                        layer = ContextLayer.L0,
+                        content = "## Operator profile\n$about",
+                        sourceType = "operatorProfile",
+                        sourceId = "operator-profile",
+                        tokenEstimate = about.length / 4,
+                        role = EntryRole.SYSTEM,
+                    ),
+                )
+            } ?: emptyList()
         var accumulatedEntries =
-            systemPrompt + journalEntries + repoMapEntries + needsEntries +
+            systemPrompt + profileEntries + journalEntries + repoMapEntries + needsEntries +
                 schemaEntries + promptEntries + steeringEntries
         val contextPack = contextPackBuilder.build(
             id = ContextPackId(UUID.randomUUID().toString()),