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>

Config/personas/cinema/exact.json

@@ -0,0 +1,5 @@
+{
+  "generation": {
+    "aspect": "2.35:1"
+  }
+}