feat: add configurable S3 object storage

Cargo.toml

@@ -2,6 +2,7 @@
 name = "imageforge"
 version = "0.1.0"
 edition = "2021"
+rust-version = "1.92"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
@@ -38,6 +39,9 @@ rand = "0.8"
 sha2 = "0.10"
 aes-gcm = "0.10"
 
+# S3-compatible object storage (Garage, MinIO, AWS S3, etc.)
+aws-sdk-s3 = { version = "1", default-features = false, features = ["rustls", "default-https-client", "rt-tokio"] }
+
 # Images
 # Keep image-rs limited to formats exposed by the API. AVIF decoding uses
 # libdav1d on Linux; encoding is handled by the direct ravif dependency.
@@ -51,6 +55,7 @@ img-parts = "0.4"
 
 # HTTP client (Stripe API)
 reqwest = { version = "0.12", default-features = false, features = ["rustls-tls", "json"] }
+url = "2"
 
 # Mail
 lettre = { version = "0.11", default-features = false, features = ["tokio1", "tokio1-rustls-tls", "builder", "smtp-transport"] }