Stop session replay obfuscation for non-EU/CA users

[ericokuma]

WHY: To enable unredacted session replays for non-EU/CA users while maintaining privacy compliance for regulated regions. This change implements capture-time masking based on user's GeoIP location, as recommended by PostHog (APP-582).

WHAT: Configured PostHog session_recording to dynamically apply masking:

• Utilizes GeoIP data to identify EU/CA users and sets an is_regulated_region person property.
• Applies a custom maskInputFn that masks inputs only for regulated users (passwords are always masked).
• Integrated into posthog.init loaded and onFeatureFlags callbacks for timely GeoIP evaluation.

Checklist:

• Covered by tests
• Ran it and it works as intended
• Reviewed the diff before requesting a review
• Checked for unhandled edge cases
• Linked the issues it closes
• Checked if the docs need to be updated. If so, create a separate Linear DOCS issue
• Intend to cherry-pick into the release branch
• I'm proud of this work!

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Linear Issue: APP-582