Minor errors in 3.0 binary format

1. The third (recursive) case of the binary definition of sN should have i:s instead of i:u

• 3.0: https://webassembly.github.io/spec/core/binary/values.html#integers
• 2.0 for comparison: https://www.w3.org/TR/wasm-core-2/#integers%E2%91%A4

2. (arguable?) The module binary definition uses * everywhere for all the section lists, but the typeid and code sections should have a distinguished arity to make in unambiguous that they must have the same number of entries as each other (while other sections are allowed to have different sizes) - 2.0 used n.

• 3.0: https://webassembly.github.io/spec/core/binary/modules.html#binary-module
• 2.0 for comparison: https://www.w3.org/TR/wasm-core-2/#modules%E2%91%A0%E2%93%AA

These were found while hand-mechanising part of the binary format in Isabelle.

Read the 3.0 binary values and modules sections linked in the issue, comparing each with the corresponding 2.0 definitions. Verify the recursive sN production and the relationship between typeid and code section arities; done means the specification reflects the intended definitions and the wording is unambiguous.