Add atomic durable job admission

crates/remora-admission/src/error.rs

@@ -0,0 +1,30 @@
+use remora_credentials::CredentialError;
+use remora_durable::DurableError;
+use remora_identity::IdentityError;
+
+#[derive(Debug, thiserror::Error)]
+pub enum AdmissionError {
+    #[error("invalid submission: {0}")]
+    Invalid(String),
+    #[error("submission is not authorized")]
+    Unauthorized,
+    #[error("idempotency key was reused with a different request")]
+    IdempotencyConflict,
+    #[error("execution grant not found")]
+    GrantNotFound,
+    #[error("configuration error: {0}")]
+    Config(String),
+    #[error(transparent)]
+    Credential(#[from] CredentialError),
+    #[error(transparent)]
+    Durable(#[from] DurableError),
+}
+
+impl From<IdentityError> for AdmissionError {
+    fn from(error: IdentityError) -> Self {
+        match error {
+            IdentityError::UnauthorizedTarget => Self::Unauthorized,
+            other => Self::Invalid(other.to_string()),
+        }
+    }
+}