branch-4.1: [opt](deps) change paimon-cpp download to tag #60694

[xylaaaaa]

pick

• [opt](deps) change paimon-cpp download to tag #60694

[Thearas]

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Please clearly describe your PR:

1. What problem was fixed (it's best to include specific error reporting information). How it was fixed.
2. Which behaviors were modified. What was the previous behavior, what is it now, why was it modified, and what possible impacts might there be.
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[Copilot]

Pull request overview

Backports the dependency-source change for paimon-cpp on branch-4.1 by switching from a direct git clone of the upstream repository to downloading a versioned doris-thirdparty tag tarball, improving reproducibility and aligning with other thirdparty dependency handling.

Changes:

• Replace paimon-cpp git-based source configuration with a doris-thirdparty tag tarball URL.
• Add corresponding archive name, extracted source directory name, and MD5 checksum for integrity checking.

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[xylaaaaa]

run buildall

[doris-robot]

BE UT Coverage Report

Increment line coverage 🎉

Increment coverage report
Complete coverage report

Category	Coverage
Function Coverage	52.88% (19289/36478)
Line Coverage	36.20% (180141/497589)
Region Coverage	32.71% (139281/425864)
Branch Coverage	33.75% (60611/179614)

[hello-stephen]

BE Regression && UT Coverage Report

Increment line coverage 100% (0/0) 🎉

Increment coverage report
Complete coverage report

Category	Coverage
Function Coverage	71.38% (25492/35713)
Line Coverage	54.09% (268668/496705)
Region Coverage	51.51% (221586/430139)
Branch Coverage	53.06% (95650/180259)