[sollhui]

What problem does this PR solve?

Issue Number: None

Related PR: #67510

Problem Summary: Backport #67510 to branch-4.2. Multi-table routine load rebuilds stream-load tasks when planning dynamic target tables, but omitted the job's jsonpaths and num_as_string properties. Propagate both properties so per-table plans honor the configured JSON paths and number handling.

The target branch does not contain NereidsStreamLoadTaskTest, so this backport adds the JSON-property test as a new file.

Release note

Fix multi-table routine load to honor jsonpaths and num_as_string for dynamic target tables.

Check List (For Author)

• Test: Compilation and tests skipped as requested. The original PR's unit test is included in this backport. CI requested with run buildall.
• Behavior changed: Yes. Multi-table routine load applies configured jsonpaths and num_as_string during per-table planning.
• Does this need documentation: No.

[hello-stephen]

Thank you for your contribution to Apache Doris.
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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.
3. What features were added. Why was this function added?
4. Which code was refactored and why was this part of the code refactored?
5. Which functions were optimized and what is the difference before and after the optimization?

[sollhui]

run buildall

[hello-stephen]

FE UT Coverage Report

Increment line coverage 100.00% (2/2) 🎉
Increment coverage report
Complete coverage report

[hello-stephen]

FE Regression Coverage Report

Increment line coverage 100.00% (2/2) 🎉
Increment coverage report
Complete coverage report

[github-actions]

PR approved by anyone and no changes requested.

[github-actions]

PR approved by at least one committer and no changes requested.