feat(iceberg): support iceberg connection

[chenzl25]

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What's changed and what's your intention?

• Related tracking: Connection #19637
• Support iceberg connection. Most of the iceberg properties could be specified in the iceberg connection except database.name and table.name.

Checklist

• I have written necessary rustdoc comments.
• I have added necessary unit tests and integration tests.
• I have added test labels as necessary.
• I have added fuzzing tests or opened an issue to track them.
• My PR contains breaking changes.
• My PR changes performance-critical code, so I will run (micro) benchmarks and present the results.
• My PR contains critical fixes that are necessary to be merged into the latest release.

Documentation

• My PR needs documentation updates.

Release note

• Support iceberg connection

[graphite-app]

There appears to be a stray iceberg_connection line at the end of this TOML file that should be removed. This line isn't valid TOML syntax and could interfere with proper file parsing.

Spotted by Graphite Reviewer

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[tabVersion]

LGTM