feat(http): calculate updates' and uuids' dbs size

meilisearch-http/src/helpers/env.rs

@@ -0,0 +1,16 @@
+use walkdir::WalkDir;
+
+pub trait EnvSizer {
+    fn size(&self) -> u64;
+}
+
+impl EnvSizer for heed::Env {
+    fn size(&self) -> u64 {
+        WalkDir::new(self.path())
+            .into_iter()
+            .filter_map(|entry| entry.ok())
+            .filter_map(|entry| entry.metadata().ok())
+            .filter(|metadata| metadata.is_file())
+            .fold(0, |acc, m| acc + m.len())
+    }
+}