chore: foundation/src/serialization tech debt (#2722)

Fixes #2593 

I marked the `deserializeArrayFromVector` as deprecated because we only
use it in `SiblingPath` and everywhere else we use `BufferReader`.

yarn-project/foundation/src/serialize/free_funcs.ts

@@ -79,14 +79,11 @@ export function numToUInt8(n: number) {
 }
 
 /**
- * Serialize a Buffer into a vector format by encoding the length of the buffer and concatenating it with the original buffer.
- * The resulting vector consists of a 4-byte header containing the big-endian representation of the original buffer's length, followed by the original buffer.
- * This function is useful when storing buffers as data structures with dynamic lengths and later deserializing them using 'deserializeBufferFromVector'.
- *
- * @param buf - The input Buffer to be serialized into a vector format.
- * @returns A Buffer containing the serialized vector with the encoded length header.
+ * Adds a 4-byte byte-length prefix to a buffer.
+ * @param buf - The input Buffer to be prefixed
+ * @returns A Buffer with 4-byte byte-length prefix.
  */
-export function serializeBufferToVector(buf: Buffer) {
+export function prefixBufferWithLength(buf: Buffer) {
   const lengthBuf = Buffer.alloc(4);
   lengthBuf.writeUInt32BE(buf.length, 0);
   return Buffer.concat([lengthBuf, buf]);
@@ -131,20 +128,6 @@ export function serializeDate(date: Date) {
   return serializeBigInt(BigInt(date.getTime()), 8);
 }
 
-/**
- * Deserialize a buffer from a vector by reading the length from its first 4 bytes, and then extracting the contents of the buffer.
- * The function returns an object containing the deserialized buffer as 'elem' and the number of bytes advanced ('adv') after deserialization.
- *
- * @param vector - The input buffer containing the serialized vector.
- * @param offset - The starting position from where the deserialization should begin (default is 0).
- * @returns An object with the deserialized buffer as 'elem' and the number of bytes advanced ('adv') after deserialization.
- */
-export function deserializeBufferFromVector(vector: Buffer, offset = 0) {
-  const length = vector.readUInt32BE(offset);
-  const adv = 4 + length;
-  return { elem: vector.subarray(offset + 4, offset + adv), adv };
-}
-
 /**
  * Deserialize a boolean value from a given buffer at the specified offset.
  * Reads a single byte at the provided offset in the buffer and returns
@@ -225,6 +208,7 @@ export function serializeBufferArrayToVector(arr: Buffer[]) {
  * @param vector - The input buffer containing the serialized array.
  * @param offset - An optional starting position in the buffer for deserializing the array.
  * @returns An object containing the deserialized array and the total number of bytes used during deserialization (adv).
+ * @deprecated User BufferReader instead.
  */
 export function deserializeArrayFromVector<T>(
   deserialize: (

yarn-project/foundation/src/serialize/index.ts

@@ -1,5 +1,3 @@
 export * from './free_funcs.js';
-export * from './deserializer.js';
-export * from './serializer.js';
 export * from './buffer_reader.js';
 export * from './types.js';