Container SSZ deserialize on short/empty inputs throws RangeError

[trackoor]

Describe the bug

When deserializing empty/short SSZ buffers for container types on the latest fork (electra), @chainsafe/ssz throws a raw RangeError from DataView (e.g., Attestation, AttesterSlashing, BeaconBlock) instead of a typed decode error. This was found via fuzzing Lodestar.

Expected behavior

Detect invalid/short input and throw a stable, typed decode error (not a DataView RangeError).

Steps to Reproduce

• Empty BeaconBlock:

node -e "(async()=>{const {ssz}=await import('@lodestar/types/electra');
  ssz.BeaconBlock.deserialize(Buffer.from('','hex'));})()"

• Short BeaconBlock:

node -e "(async()=>{const {ssz}=await import('@lodestar/types/electra');
  ssz.BeaconBlock.deserialize(Buffer.from('64000000a8ea7673','hex'));})()"

• Short Attestation:

node -e "(async()=>{const {ssz}=await import('@lodestar/types/electra');
  ssz.Attestation.deserialize(Buffer.from('04ff','hex'));})()"

• Short AttesterSlashing:

node -e "(async()=>{const {ssz}=await import('@lodestar/types/electra');
  ssz.AttesterSlashing.deserialize(Buffer.from('01ff','hex'));})()"

• Observed (common):

RangeError: Offset is outside the bounds of the DataView
    at DataView.prototype.getUint32 (<anonymous>)
    at readVariableOffsets (.../node_modules/@chainsafe/ssz/lib/type/container.js:341:29)
    at ContainerType.getFieldRanges (.../node_modules/@chainsafe/ssz/lib/type/container.js:310:25)
    at ContainerType.value_deserializeFromBytes (file:///Users/hanzhi/node_modules/@chainsafe/ssz/lib/type/container.js:145:34)
    at ContainerType.deserialize (.../node_modules/@chainsafe/ssz/lib/type/abstract.js:42:21)
    at [eval]:2:19

Desktop:

• OS: Ubuntu 22.04
• Version: Node v20.x; @lodestar/types 1.34.1; @chainsafe/ssz 1.2.2
• Branch: ssz-v1.2.2
• Commit hash: 7f5580c