Add thiserror instead of exposing eyre anonymous errors

The change here is to make it easier for the consumer to debug the api.
Such that they can `match` on individual errors instead of having to
parse text.

eyre is convenient, but mostly from a consumers perspective

crates/dagger-sdk/src/errors.rs

@@ -0,0 +1,27 @@
+use thiserror::Error;
+
+#[derive(Error, Debug)]
+pub enum ConnectError {
+    #[error("failed to connect to dagger engine")]
+    FailedToConnect(#[source] eyre::Error),
+}
+
+#[derive(Error, Debug)]
+pub enum DaggerError {
+    #[error("failed to build dagger internal graph")]
+    Build(#[source] eyre::Error),
+    #[error("failed to parse input type")]
+    Serialize(#[source] eyre::Error),
+    #[error("failed to query dagger engine: {0}")]
+    Query(#[source] dagger_core::graphql_client::GraphQLError),
+    #[error("failed to unpack response")]
+    Unpack(#[source] DaggerUnpackError),
+}
+
+#[derive(Error, Debug)]
+pub enum DaggerUnpackError {
+    #[error("Too many nested objects inside graphql response")]
+    TooManyNestedObjects,
+    #[error("failed to deserialize response")]
+    Deserialize(#[source] serde_json::Error),
+}