Add ByteSize() to TypeInfo interface

[fxamacker]

Updates #292

Description

This PR adds ByteSize() function in TypeInfo interface, which is used to compute extra data size of inlined registers.

Context

Inlined registers are treated as element and its encoded size must be known at runtime to enforce slab size limits. Since inlined registers are root slabs with extra data, encoded extra data size needs to be computed.

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• Targeted PR against main branch
• Linked to Github issue with discussion and accepted design OR link to spec that describes this work
• Code follows the standards mentioned here
• Updated relevant documentation
• Re-reviewed Files changed in the Github PR explorer
• Added appropriate labels

[fxamacker]

Postponing merge (for now) because I found a better approach and am looking into it to see if it works out.

[fxamacker]

Closing this PR because I found a better approach.