feat: implement export-v2 chunked data export flow

[fengjiachun]

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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]

Summary of Changes

Hello, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request significantly enhances the export-v2 CLI command by introducing a chunked data export mechanism. This change allows for more granular and resilient data exports, particularly for large datasets, by dividing the export into manageable time-based chunks. It lays the groundwork for a more robust data management pipeline, while temporarily restricting full snapshot imports until the corresponding data import logic is in place.

Highlights

• Chunked Data Export Implementation: Implemented a new chunked data export flow for the export-v2 CLI command, allowing data to be exported in time-based segments.
• New Modules for Export V2: Introduced chunker, coordinator, and data modules within export_v2 to handle chunk generation, export orchestration, and SQL COPY DATABASE statement construction, respectively.
• Export Command Enhancements: The export-v2 create command now supports a --chunk-time-window option for defining chunk sizes and includes improved validation for time ranges.
• Manifest Updates: The export manifest (manifest.rs) has been extended to store chunk metadata, track chunk status (InProgress, Completed, Skipped, Failed), and parse time ranges from input.
• Import Command Restrictions: The import-v2 command now explicitly rejects importing full snapshots that contain data chunks, as the data import functionality for these snapshots is not yet implemented.
• Object Storage Utilities: Added create_dir_all and list_files_recursive methods to the SnapshotStorage trait and its OpenDalStorage implementation to support directory creation and file listing in object storage.

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[gemini-code-assist]

Code Review

This pull request implements the chunked data export flow for export-v2, a significant feature enhancement. The changes are well-structured, introducing new modules for chunking, coordination, and data handling, which improves modularity. The implementation correctly handles resumable exports by updating a manifest file at each step of the process. New error types and comprehensive tests have been added. I've included one suggestion to improve code clarity by reducing duplication in the export coordinator.

[chatgpt-codex-connector]

💡 Codex Review

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Reviewed commit: 4e6af2c307

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[discord9]

rest LGTM