feat(audience): rename event property keys to snake_case [SDK-412]

[nattb8]

Renames all multi-word Audience event property keys from camelCase to snake_case to align with industry standard (Segment, GA4). Event names were already snake_case; this makes properties consistent.

UTM params and click IDs (utm_source, gclid, etc.) are unchanged — they were already snake_case.

Fixes SDK-412.

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Note

Medium Risk
Breaking change to the emitted/typed event payload schema by renaming many properties (including session_id) from camelCase to snake_case across both the Pixel and Web SDK, which can impact downstream analytics pipelines and consumers expecting old keys.

Overview
Standardises Audience event property keys to snake_case across the stack. The Pixel now emits session_id, form_*, field_names, link_*, and email_hash instead of their camelCase equivalents, and includes third-party cookie IDs as ga_client_id / fb_click_id / fb_browser_id.

The Web SDK’s typed event property interfaces (e.g. game_id, item_id, transaction_id, duration_sec) and runtime message construction were updated accordingly so page, track, session_start, and session_end all carry session_id.

Docs, sample app field metadata, and test suites were updated to match the new property names.

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☁️ Nx Cloud last updated this comment at 2026-05-22 02:53:28 UTC

[github-actions]

✅ Pixel Bundle Size — @imtbl/pixel

Metric	Size	Delta vs main
Gzipped	6347 bytes (6.19 KB)	-3 bytes
Raw (minified)	17468 bytes	+18 bytes

Budget: 10.00 KB gzipped (warn at 8.00 KB)

[github-actions]

✅ Audience Bundle Size — @imtbl/audience

Metric	Size	Delta vs main (60a837f)
Gzipped	18710 bytes (18.27 KB)	+6 bytes
Raw (minified)	54679 bytes	+4 bytes

Budget: 24.00 KB gzipped (warn at 20.00 KB)

[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

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