feat: aggr stats partial eval

[discord9]

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What's changed and what's your intention?

mostly test

PR Checklist

Please convert it to a draft if some of the following conditions are not met.

• I have written the necessary rustdoc comments.
• I have added the necessary unit tests and integration tests.
• This PR requires documentation updates.
• API changes are backward compatible.
• Schema or data changes are backward compatible.

[gemini-code-assist]

Code Review

This pull request introduces the AggregateStats physical optimizer pass, which optimizes aggregate queries by synthesizing partial states from per-file statistics instead of scanning eligible files. It supports MIN, MAX, and COUNT for append-only tables and includes updates to RegionScanExec to handle file exclusion. A performance improvement opportunity was identified regarding the eager materialization of statistics for all columns, which could be optimized by only processing columns required for the specific aggregate.

[gemini-code-assist]

Eagerly materializing statistics for all field columns in every file can lead to significant overhead in tables with many columns. Consider passing the set of required columns to build_scan_input_stats to avoid unnecessary metadata processing.

[discord9]

Closed by #8046