refactor kv get rows 2.1.x - #9988

Change Description

This PR refactors read_only::get_kv_table_rows and fixes the following problems

• prevent combining --lower/--upper with --index
• don't treat empty string the same as not present for lower_bound, upper_bound, or index_value
• support default encode type for get_kv_table_rows
• implement show payer option
• remove get_kv_table_rows RPC timing constraint

Change Type

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• Documentation

• Stability bug fix

• Other

• Other - special case

Testing Changes

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• New Tests

• Existing Tests

• Test Framework

• CI System

• Other

Consensus Changes

• Consensus Changes

API Changes

• API Changes

Documentation Additions

• Documentation Additions