feat: implement local-files feature with various enhancements and cleanup

k-tv-backend/api/src/routes/files.rs

@@ -53,6 +53,7 @@ pub fn router() -> Router<AppState> {
 // Direct streaming
 // ============================================================================
 
+#[cfg_attr(not(feature = "local-files"), allow(unused_variables))]
 async fn stream_file(
     State(state): State<AppState>,
     Path(encoded_id): Path<String>,
@@ -131,7 +132,7 @@ async fn stream_file(
             );
         }
 
-        return builder.body(body).map_err(|e| ApiError::internal(e.to_string()));
+        builder.body(body).map_err(|e| ApiError::internal(e.to_string()))
     }
 
     #[cfg(not(feature = "local-files"))]
@@ -316,6 +317,7 @@ async fn clear_transcode_cache(
 // Helpers
 // ============================================================================
 
+#[cfg(feature = "local-files")]
 fn content_type_for_ext(ext: &str) -> &'static str {
     match ext {
         "mp4" | "m4v" => "video/mp4",
@@ -327,6 +329,7 @@ fn content_type_for_ext(ext: &str) -> &'static str {
     }
 }
 
+#[cfg(feature = "local-files")]
 fn parse_range(range: &str, file_size: u64) -> Option<(u64, u64)> {
     let range = range.strip_prefix("bytes=")?;
     let (start_str, end_str) = range.split_once('-')?;