feat: moved lua scripts to new cache structure

server/src/_luaScriptsV2/fullSubject/updateEntityDataV2.lua

@@ -0,0 +1,55 @@
+--[[
+  Lua Script: Update Entity Data in FullSubject V2 Redis Cache
+
+  Atomically updates top-level entity fields in the cached FullSubject JSON.
+
+  KEYS[1] = FullSubject cache key (entity-specific)
+
+  ARGV[1] = updates JSON object
+  ARGV[2] = cache TTL in seconds
+  ARGV[3] = current timestamp in ms
+
+  Returns JSON:
+    { "success": true, "updated_fields": ["spend_limits", "usage_alerts"] }
+    or
+    { "success": false, "cache_miss": true }
+    or
+    { "success": false, "no_entity": true }
+]]
+
+local subject_key = KEYS[1]
+local updates = cjson.decode(ARGV[1])
+local cache_ttl = tonumber(ARGV[2])
+local now_ms = tonumber(ARGV[3])
+
+local has_updates = false
+for _ in pairs(updates) do
+  has_updates = true
+  break
+end
+
+if not has_updates then
+  return cjson.encode({ success = true, updated_fields = {} })
+end
+
+local current_raw = redis.call("GET", subject_key)
+if not current_raw then
+  return cjson.encode({ success = false, cache_miss = true })
+end
+
+local cached = cjson.decode(current_raw)
+
+if not cached.entity then
+  return cjson.encode({ success = false, no_entity = true })
+end
+
+local updated_fields = {}
+
+for field_name, field_value in pairs(updates) do
+  cached.entity[field_name] = field_value
+  table.insert(updated_fields, field_name)
+end
+
+redis.call("SET", subject_key, cjson.encode(cached), "EX", cache_ttl)
+
+return cjson.encode({ success = true, updated_fields = updated_fields })