[v1] Cleanup the BlockTable in InputBatch

[heheda12345]

This pr cleans up the BlockTable class by:

1. removing max_model_len which is not used in this class
2. removing start argument in append_row and get this value from self.num_blocks_per_row
3. moving block_id to the first argument of append_row and add_row.

2 & 3 are preparations of hybrid memory allocator (#11382). For hybrid models, different layers will have different BlockTable instances, and I want to broadcast the operations on BlockTable to all these BlockTable instances with exact the same arguments except different block_id, so I need (2) as the start can be different and (3) to support passing different block_id values.

Split from #13296

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[comaniac]

LGTM

[comaniac]

I'm not very familiar with this. Does this always equal to len(req_state.block_ids) - len(req_data.new_block_ids) if not 0?

[heheda12345]

I think so, and added some tests for the checking block_table is the same as req_state.block_ids