Refactor file type checking for better consistency

Fix tests

src/lib.rs

@@ -7,6 +7,7 @@ pub mod data;
 pub mod database;
 pub mod error;
 pub mod exif;
+pub mod file_types;
 pub mod files;
 pub mod geo;
 pub mod memories;
@@ -36,7 +37,6 @@ pub fn update_media_counts(_media_dir: &Path) {
     // Stub - implemented in main.rs
 }
 
-pub fn is_video(_entry: &DirEntry) -> bool {
-    // Stub - implemented in main.rs
-    false
+pub fn is_video(entry: &DirEntry) -> bool {
+    file_types::direntry_is_video(entry)
 }