Feat(): distributed caching (#13435)

RESOLVES CORE-1153

**What**
- This pr mainly lay the foundation the caching layer. It comes with a modules (built in memory cache) and a redis provider.
- Apply caching to few touch point to test

Co-authored-by: Carlos R. L. Rodrigues <37986729+carlos-r-l-rodrigues@users.noreply.github.com>

packages/medusa/src/feature-flags/caching.ts

@@ -0,0 +1,10 @@
+import { FlagSettings } from "@medusajs/framework/feature-flags"
+
+const CachingFeatureFlag: FlagSettings = {
+  key: "caching",
+  default_val: false,
+  env_key: "MEDUSA_FF_CACHING",
+  description: "[WIP] Enable core caching where applicable",
+}
+
+export default CachingFeatureFlag