ADD thumbnail to database (#12)

* ADD thumbnail to database

* ADD thumbnail generation and retrieval functionality

* ADD thumbnail availability check in VideoCard component

* ADD ClipDTO to reduce exposed internals

* REFactor move APIResponse and VideoMetadata to dto package

* REMOVE unused props from VideoCard

* ADD isThumbnailAvailable function

src/main/resources/application.properties

@@ -6,7 +6,7 @@ spring.servlet.multipart.max-file-size=2GB
 spring.servlet.multipart.max-request-size=2GB
 storage.temp.inputs=videos/inputs/
 storage.temp.outputs=videos/outputs/
-storage.outputs=videos/clips/
+storage.outputs=outputs/
 
 ## Server Configuration
 server.servlet.session.timeout=30m

src/main/resources/db/schema.sql

@@ -23,5 +23,6 @@ CREATE TABLE IF NOT EXISTS clips (
     duration FLOAT NOT NULL,
     file_size FLOAT NOT NULL,
     video_path VARCHAR(255) NOT NULL,
+    thumbnail_path VARCHAR(255) NOT NULL,
     FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE
 );