[WIP][FEAT]: Add module decoder_vbi in lib_ccxr

[vatsalkeshav]

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This PR migrates /src/lib_ccx/ccx_decoders_vbi.c to rust.
These changes have been made-

1. Pure rust equivalent functions in /src/rust/lib_ccxr/src/decoder_isdb/functions_vbi_main.rs (helpers in functions_vbi_slice.rs, functions_vbi_decode.rs, vbi_service_table.rs)
2. Required datatypes in /src/rust/lib_ccxr/src/decoder_isdb, structs_xds.rs, structs_isdb.rs, structs_ccdecode.rs, structs_vbi_slice.rs, structs_vbi_decode.rs
3. Exit codes etc in /src/rust/lib_ccxr/src/decoder_isdb/exit_codes.rs