[opt](inverted index) Add null document interface to optimize empty s…

[qidaye]

…tring indexing (#28661)

Proposed changes

pick from #28661

Further comments

If this is a relatively large or complex change, kick off the discussion at dev@doris.apache.org by explaining why you chose the solution you did and what alternatives you considered, etc...

[qidaye]

run buildall

[github-actions]

clang-tidy review says "All clean, LGTM! 👍"

[doris-robot]

TeamCity be ut coverage result:
Function Coverage: 37.75% (7993/21173)
Line Coverage: 29.45% (64934/220491)
Region Coverage: 28.92% (33405/115506)
Branch Coverage: 24.79% (17140/69132)
Coverage Report: http://coverage.selectdb-in.cc/coverage/da76fced2114088b16038f7e01390ead78103dd0_da76fced2114088b16038f7e01390ead78103dd0/report/index.html

[doris-robot]

(From new machine)TeamCity pipeline, clickbench performance test result:
the sum of best hot time: 51.41 seconds
stream load tsv: 586 seconds loaded 74807831229 Bytes, about 121 MB/s
stream load json: 20 seconds loaded 2358488459 Bytes, about 112 MB/s
stream load orc: 65 seconds loaded 1101869774 Bytes, about 16 MB/s
stream load parquet: 32 seconds loaded 861443392 Bytes, about 25 MB/s
insert into select: 30.3 seconds inserted 10000000 Rows, about 330K ops/s
storage size: 17162002097 Bytes