feat: Support and tests for person batch exports in Postgres

[tomasfarias]

Problem

PR Adds support for person batch exports for Snowflake. Works the same as its Bigquery (#23187) and Snowflake (#23333) equivalents.

Changes

👉 Stay up-to-date with PostHog coding conventions for a smoother review.

Does this work well for both Cloud and self-hosted?

How did you test this code?

[github-actions[bot]]

Size Change: +2 B (0%)

Total Size: 1.06 MB

ℹ️ View Unchanged

| Filename | Size | Change | | :--- | :---: | :---: | | `frontend/dist/toolbar.js` | 1.06 MB | +2 B (0%) |

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