feat(medusa-plugin-meilisearch): Update + improve Meilisearch plugin (#3377)

* feat(medusa-plugin-meilisearch): Upgrade meilisearch deps + migrate plugin to TS

* fix version

* Remove transaction base service from search service

* Create .changeset/strange-mails-pump.md

* Backward compatibility

* Address PR feedback

* Fix folder structure

* Update readme

* Move types

* fix deps

* Change version in changeset

---------

Co-authored-by: adrien2p <adrien.deperetti@gmail.com>

.changeset/strange-mails-pump.md

@@ -0,0 +1,65 @@
+---
+"medusa-plugin-meilisearch": major
+"@medusajs/medusa": patch
+---
+
+feat(medusa-plugin-meilisearch): Update + improve Meilisearch plugin
+
+**What**
+- Bumps `meilisearch` dep to latest major
+- Migrates plugin to TypeScript
+- Changes the way indexes are configured in `medusa-config.js`:
+
+**Before**
+```
+{
+    resolve: `medusa-plugin-meilisearch`,
+    options: {
+      config: { host: "...", apiKey: "..." },
+      settings: {
+        products: {
+          searchableAttributes: ["title"],
+          displayedAttributes: ["title"],
+        },
+      },
+    },
+  },
+```
+
+**After**
+```
+{
+    resolve: `medusa-plugin-meilisearch`,
+    options: {
+      config: { host: "...", apiKey: "..." },
+      settings: {
+        products: {
+          **indexSettings**: {
+            searchableAttributes: ["title"],
+            displayedAttributes: ["title"],
+          },
+        },
+      },
+    },
+  },
+```
+
+This is done to allow for additional configuration of indexes, that are not necessarily passed on query-time. 
+
+We introduce two new settings:
+```
+settings: {
+  products: {
+    indexSettings: {
+      searchableAttributes: ["title"],
+      displayedAttributes: ["title"],,
+    },
+    primaryKey: "id"
+    transformer: (document) => ({ id: "yo" })
+  },
+},
+```
+
+Meilisearch changed their primary key inference in the major release. Now we must be explicit when multiple properties end with `id`. Read more in their [docs](https://docs.meilisearch.com/learn/core_concepts/primary_key.html#primary-field).
+
+The transformer allows developers to specify how their documents are stored in Meilisearch. It is configurable for each index.