Premium Analytics: add Stats email time series endpoints

[kangzj]

Fixes #

Proposed changes

• Add Premium Analytics data package support for the Stats email time series endpoint, following the Stats endpoint patterns established in Premium Analytics: add Stats endpoint foundation #49886.
• Wire the endpoint-specific query, hook, public exports, and sanitizer/normalizer registration where applicable.
• Keep endpoint typing tied to sanitizer keys or passthrough query inference, with focused fixtures/tests for the raw endpoint payload shape where normalization is introduced.

Related product discussion/links

• Builds on Premium Analytics: add Stats endpoint foundation #49886.

Does this pull request change what data or activity we track or use?

No. This only adds typed client data/query integration for an existing Stats API endpoint.

Testing instructions

• pnpm --dir projects/packages/premium-analytics test -- packages/data/src/queries/tests/stats-queries.test.ts packages/data/src/hooks/tests/stats-exports.test.ts --runInBand
• pnpm exec eslint --max-warnings=0
• pnpm --dir projects/packages/premium-analytics run typecheck
• git diff --check

[jp-launch-control]

Code Coverage Summary

This PR did not change code coverage!

That could be good or bad, depending on the situation. Everything covered before, and still is? Great! Nothing was covered before? Not so great. 🤷

Full summary · PHP report

[github-actions]

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[kangzj]

Review-cycle audit complete: the latest branch state includes the requested postId guards, no actionable invited-reviewer or owner feedback remains, and GitHub reports no required checks for this branch. Current CI snapshot shows the main build, typecheck, JS/PHP tests, lint, and changelog checks passing; only non-required coverage/label bookkeeping remains pending. Local audit: jp test js packages/premium-analytics skipped because the project has no test-js composer script; jp build packages/premium-analytics -v built the package successfully, then failed at the final boot asset copy with an existing-file EACCES permission error.