Tracking: File Source (GCS, S3) improvements and bug fixes

[kwannoel]

• Better error messages for parquet schema mismatch #20409
• /risingwave/src/meta/src/controller/streaming_job.rs:1390:9: source id should be used by at least one fragment #20618
• Use a table function to read the backfill progress of file source #20652
• bug: slow reading from file source when there's a lot of files #20915
• bug: single file in match prefix cannot be read #20916
• Source metrics for file source #20931

[github-actions]

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