docs: relax encoded paylaod padding (#2226)

relax encoded paylaod padding

Author: bxue-l2

docs/spec/src/integration/spec/3-data-structs.md

@@ -24,7 +24,7 @@ The header carries metadata needed to decode back to the original payload. Becau
 
 Version 0x0 specifies the following transformation from the original payload to a sequence of field element:
 - For every 31 bytes of the payload, insert a zero byte to produce a 32-byte value that is a valid field element.
-- Zero-pad the final chunk so the payload length is a multiple of 32 bytes, and ensure the encoded payload comprises a power-of-two number of 32-byte field elements (32, 64, 128, 256, …) to match EigenDA blob sizing.
+- Pad the final chunk so the payload length is a multiple of 32 bytes, and ensure the encoded payload comprises a power-of-two number of 32-byte field elements (32, 64, 128, 256, …) to match EigenDA blob sizing. We recommend to use 0 for all padding for encoded payload.
 
 ```solidity
 [0x00, version_byte, big-endian uint32 len(payload), 0x00, 0x00,...] +