What problem does this PR solve?

Issue Number: close #9692

Problem Summary: Reduce virtual function call for key_serialize and key_string.

1. For key_serialized, batch-wise serialization/deserialization can reduce virtual function call (Also enable prefetch for key_serialized, because we can batch get hash after this pr)
2. For key_string, batch-wise sortKey can reduce virtual function call.

Workload: tpch-50g
Queries: same with #9679

  # --q5 Q3-1: key_serialized as group by method;  33/300M; HashMap with StringRef key
  "select /*+ mpp_1phase_agg() */ sum(l_discount), l_returnflag from lineitem group by l_returnflag, l_discount;"
  # --q6 Q3-2: key_serialized as group by method; 77M/300M; HashMap with StringRef key
  "select /*+ mpp_1phase_agg() */ sum(l_discount) as csum, l_returnflag from lineitem group by l_returnflag, l_discount, l_extendedprice having csum > 100;"


  # --q7 Q4-1: two_keys_num64_strbinpadding: 21/300M; HashMap with StringRef key
  "select /*+ mpp_1phase_agg() */ sum(l_discount) from lineitem group by l_returnflag, L_LINENUMBER;"
  # --q8 Q4-2: two_keys_num64_strbinpadding; 29.9M/300M; HashMap with StringRef key
  "select /*+ mpp_1phase_agg() */ sum(l_discount) as csum, l_partkey from lineitem group by l_returnflag, l_partkey having csum > 100;"
 

Workload: clickbench
Queries: https://github.com/ClickHouse/ClickBench/blob/fdfdb5d94f2a668dce1f63d55498aa34510e4c9c/clickhouse/queries.sql#L11

NOTE:

1. nightly-20250205 commit: fe563a1; opt-batch commit: f20224a
2. For Q4-1/Q4-2, nightly key is two_keys_num64_strbinpadding. opt key is key_serialized.

What is changed and how it works?

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No code

Side effects

• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Breaking backward compatibility

Documentation

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Changes MySQL compatibility

Release note

None