feat(sdk): with _opts methods

Now all opt values enter into a _opts function instead of the original.
This avoids a lot of verbosity for both None in the case opts are
unwanted, and Some() if they actually are.

They are used like so:

```rust
client.container().from("...");
client.container_opts(Some(ContainerOpts{ ... }))
```

Some from opts will be removed in a future commit/pr

crates/dagger-sdk/examples/first-pipeline/main.rs

@@ -2,9 +2,9 @@ fn main() -> eyre::Result<()> {
     let client = dagger_sdk::connect()?;
 
     let version = client
-        .container(None)
+        .container()
         .from("golang:1.19")
-        .with_exec(vec!["go", "version".into()], None)
+        .with_exec(vec!["go", "version".into()])
         .stdout()?;
 
     println!("Hello from Dagger and {}", version.trim());