[improvement](build) Add build and unit test parallel options to run-fe-ut.sh

[heguanhui]

What problem does this PR solve?

Issue Number: close #xxx

Problem Summary: run-fe-ut.sh does not support build concurrency or unit test execution concurrency. The FE pom.xml already supports the fe_ut_parallel variable (via env.FE_UT_PARALLEL) to control maven-surefire-plugin forkCount, but run-fe-ut.sh never passes this variable, defaulting to 1 JVM for unit tests. This makes FE unit test execution very slow.

Release note

Add -j and -p options to run-fe-ut.sh to support build parallelism and unit test parallelism respectively. -j <num> controls Maven build thread count (passed as -T), and -p <num> controls the number of forked JVMs for running unit tests (passed as FE_UT_PARALLEL env variable which maps to forkCount in maven-surefire-plugin).

Check List (For Author)

• Test

  • Manual test

• Behavior changed:

  • No.

• Does this need documentation?

  • No.

Check List (For Reviewer who merge this PR)

• Confirm the release note
• Confirm test cases
• Confirm document
• Add branch pick label

[hello-stephen]

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