feat: Add EncodingError

Change method signatures to expect it and raise it where it makes sense

--- don't change below this line ---
ENG-4076 <#DTT#>

src/encoding/errors.rs

@@ -0,0 +1,31 @@
+use std::io;
+
+use thiserror::Error;
+
+/// Represents the outer-level, user-facing errors of the tycho-execution encoding package.
+///
+/// `EncodingError` encompasses all possible errors that can occur in the package,
+/// wrapping lower-level errors in a user-friendly way for easier handling and display.
+/// Variants:
+/// - `InvalidInput`: Indicates that the encoding has failed due to bad input parameters.
+/// - `FatalError`: There is problem with the application setup.
+#[derive(Error, Debug)]
+#[allow(dead_code)]
+pub enum EncodingError {
+    #[error("Invalid input: {0}")]
+    InvalidInput(String),
+    #[error("Fatal error: {0}")]
+    FatalError(String),
+}
+
+impl From<io::Error> for EncodingError {
+    fn from(err: io::Error) -> Self {
+        EncodingError::FatalError(err.to_string())
+    }
+}
+
+impl From<serde_json::Error> for EncodingError {
+    fn from(err: serde_json::Error) -> Self {
+        EncodingError::FatalError(err.to_string())
+    }
+}