notify users to update their build scripts if using rocksdb or sha256_media

Signed-off-by: strawberry <strawberry@puppygock.gay>

src/core/Cargo.toml

@@ -45,6 +45,10 @@ zstd_compression =[]
 perf_measurements = []
 sentry_telemetry = []
 
+# these do nothing, these are purely for informing users to update their build scripts if they use one
+rocksdb = []
+sha256_media = []
+
 [dependencies]
 argon2.workspace = true
 axum.workspace = true

src/core/config/check.rs

@@ -6,6 +6,17 @@ use tracing::{debug, error, info, warn};
 use crate::{error::Error, Config};
 
 pub fn check(config: &Config) -> Result<(), Error> {
+	#[cfg(feature = "rocksdb")]
+	warn!(
+		"Note the rocksdb feature was deleted from conduwuit, sqlite was deleted and RocksDB is the only supported \
+		 backend now. Please update your build script to remove this feature."
+	);
+	#[cfg(feature = "sha256_media")]
+	warn!(
+		"Note the sha256_media feature was deleted from conduwuit, it is now fully integrated in a \
+		 forwards-compatible way. Please update your build script to remove this feature."
+	);
+
 	config.warn_deprecated();
 	config.warn_unknown_key();