Add exact KV memory with persona overlays and param priority.

Canonical defaults live in exact.json (UI fills empties without an LLM call); chat session overrides beat file defaults until clear/persona change.

Co-authored-by: Cursor <cursoragent@cursor.com>

AssistentConfig.cs

@@ -319,6 +319,9 @@ public sealed class AssistentConfig
 
     public JObject LoadUi(string personaId) => MergeJsonLayers("ui.json", LayerRoots(personaId));
 
+    /// <summary>Exact (KV) memory: bundled base → persona overlays → disk overlays. Persona keys overwrite base.</summary>
+    public JObject LoadExact(string personaId) => MergeJsonLayers("exact.json", LayerRoots(personaId));
+
     public JObject LoadModelProfile(string personaId)
     {
         JObject assistant = LoadAssistant(personaId);
@@ -712,6 +715,7 @@ public sealed class AssistentConfig
         JObject assistant = LoadAssistant(id);
         JObject ui = LoadUi(id);
         JObject model = LoadModelProfile(id);
+        JObject exact = LoadExact(id);
         var packs = ListPacks(id);
         var skills = ListSkills(id);
         var personas = ListPersonaCatalog();
@@ -724,6 +728,7 @@ public sealed class AssistentConfig
             ["assistant"] = assistant,
             ["ui"] = ui,
             ["model"] = model,
+            ["exact"] = exact,
             ["packs"] = new JArray(packs.Select(p => new JObject
             {
                 ["id"] = p.id,