Add thumbnail endpoint with size options

examples/thumbnail.rs

@@ -0,0 +1,50 @@
+//! Example: Download asset thumbnails
+
+use immich_sdk::Client;
+use immich_sdk::models::AssetMediaSize;
+use std::fs;
+
+#[tokio::main]
+async fn main() -> Result<(), Box<dyn std::error::Error>> {
+    // Create a client
+    let client = Client::from_url("https://immich.example.com")?.with_api_key("your-api-key");
+
+    // Asset ID to download thumbnail for
+    let asset_id = "your-asset-id-here".parse()?;
+
+    // Download thumbnail (small size, default)
+    println!("Downloading thumbnail...");
+    let thumbnail = client
+        .assets()
+        .thumbnail(asset_id)
+        .size(AssetMediaSize::Thumbnail)
+        .execute()
+        .await?;
+
+    fs::write("/path/to/output/thumbnail.jpg", &thumbnail)?;
+    println!("Saved thumbnail: {} bytes", thumbnail.len());
+
+    // Download preview (medium size)
+    let preview = client
+        .assets()
+        .thumbnail(asset_id)
+        .size(AssetMediaSize::Preview)
+        .execute()
+        .await?;
+
+    fs::write("/path/to/output/preview.jpg", &preview)?;
+    println!("Saved preview: {} bytes", preview.len());
+
+    // Download fullsize
+    let fullsize = client
+        .assets()
+        .thumbnail(asset_id)
+        .size(AssetMediaSize::Fullsize)
+        .execute()
+        .await?;
+
+    fs::write("/path/to/output/fullsize.jpg", &fullsize)?;
+    println!("Saved fullsize: {} bytes", fullsize.len());
+
+    Ok(())
+}