Batch inserts [MOD-555] (#726)

* Batch a bunch of inserts, but still more to do

* Insert many for clickhouse (+ tests)

* Batch the remaining ones except those requiring deduplication

* Risky dedups

* Bit o cleanup and formatting

* cargo sqlx prepare

* Add test around batch editing project categories

* Add struct to satisfy clippy

* Fix silly mistake that was caught by the tests!

* Leave room for growth in dummy_data

src/clickhouse/mod.rs

@@ -6,8 +6,12 @@ mod fetch;
 pub use fetch::*;
 
 pub async fn init_client() -> clickhouse::error::Result<clickhouse::Client> {
-    let database = dotenvy::var("CLICKHOUSE_DATABASE").unwrap();
+    init_client_with_database(&dotenvy::var("CLICKHOUSE_DATABASE").unwrap()).await
+}
 
+pub async fn init_client_with_database(
+    database: &str,
+) -> clickhouse::error::Result<clickhouse::Client> {
     let client = {
         let mut http_connector = HttpConnector::new();
         http_connector.enforce_http(false); // allow https URLs