feat(settings): replace highlightsFirstEnabled with highlightsPlacement

[pnvasanth]

Summary

Some users wanted to disable the Happening Now card entirely, not just choose between random vs pinned placement. Replaces the highlightsFirstEnabled boolean with a 3-state highlightsPlacement enum:

• default — current behavior (random slot within the first half of page one)
• pinned — slot 0 (what highlightsFirstEnabled: true did)
• disabled — no highlight is injected at all

How disabling works end-to-end

FeedPreferencesConfigGenerator.generate() checks the user's stored highlightsPlacement and:

• pinned → sets config.highlights_first = true (daily-feed pins to slot 0)
• disabled → sets config.highlights_limit = 0 (daily-feed's existing HighlightsLimit > 0 guard skips injection — no daily-feed change required)
• default / unset → no override

Migration

The highlightsFirstEnabled boolean is removed cleanly. Anyone who toggled "pin" since the feature shipped resets to default and can pick the new placement.

Supersedes

• Closes fix(settings): expose highlightsFirstEnabled in boot flags #3866 (the boot-exposure fix is folded into this PR via transformSettingFlags).

Test plan

• pnpm run lint clean
• __tests__/integrations/feed.ts — three new cases asserting pinned/disabled/default behavior end-to-end through FeedPreferencesConfigGenerator
• __tests__/settings.ts — mutation round-trip + invalid-enum rejection
• __tests__/boot.ts — boot settings.flags assertion updated
• Snapshot updated
• CI runs full Jest suite

[pulumi]

🍹 The Update (preview) for dailydotdev/api/prod (at 7094b83) was successful.

✨ Neo Explanation

Routine deployment of the `highlightsPlacement` enum feature with accompanying DB and Clickhouse migrations; the main non-obvious risk is that existing users with `highlightsFirstEnabled: true` may lose that preference unless the migration explicitly backfills `highlightsPlacement: 'pinned'`. ✅ Low Risk (assuming migration handles backfill).

This deployment rolls out the highlightsPlacement feature — replacing the boolean highlightsFirstEnabled flag with a tri-state enum (default, pinned, disabled) that gives the feed service finer control over highlights positioning. The FeedPreferencesConfigGenerator now maps pinned → highlights_first: true, disabled → highlights_limit: 0, and default → no change (pass-through).

Both DB and Clickhouse migration jobs are being cycled to the new commit hash (47b6fa8e), indicating schema or data migrations accompany this change — likely adding/renaming the highlightsPlacement column in SettingsFlags.

🔵 Info — The SettingsFlags schema change is backward-compatible at the application level: existing users with no highlightsPlacement set will fall through to the default case (pass-through behavior), which is equivalent to the old highlightsFirstEnabled: false default. However, any users who previously had highlightsFirstEnabled: true will not be automatically migrated to highlightsPlacement: 'pinned' — their highlights-first behavior will be lost unless the DB migration handles this backfill.

Resource Changes

    Name                                                       Type                           Operation
~   vpc-native-rotate-daily-quests-cron                        kubernetes:batch/v1:CronJob    update
~   vpc-native-worker-job-deployment                           kubernetes:apps/v1:Deployment  update
~   vpc-native-channel-highlights-cron                         kubernetes:batch/v1:CronJob    update
~   vpc-native-update-views-cron                               kubernetes:batch/v1:CronJob    update
+   vpc-native-api-db-migration-47b6fa8e                       kubernetes:batch/v1:Job        create
~   vpc-native-update-current-streak-cron                      kubernetes:batch/v1:CronJob    update
~   vpc-native-generate-search-invites-cron                    kubernetes:batch/v1:CronJob    update
-   vpc-native-api-clickhouse-migration-ab4ae3d7               kubernetes:batch/v1:Job        delete
~   vpc-native-sync-subscription-with-cio-cron                 kubernetes:batch/v1:CronJob    update
~   vpc-native-user-profile-analytics-clickhouse-cron          kubernetes:batch/v1:CronJob    update
~   vpc-native-personalized-digest-deployment                  kubernetes:apps/v1:Deployment  update
~   vpc-native-clean-channel-highlights-cron                   kubernetes:batch/v1:CronJob    update
~   vpc-native-post-analytics-clickhouse-cron                  kubernetes:batch/v1:CronJob    update
~   vpc-native-rotate-weekly-quests-cron                       kubernetes:batch/v1:CronJob    update
~   vpc-native-calculate-top-readers-cron                      kubernetes:batch/v1:CronJob    update
~   vpc-native-update-tag-materialized-views-cron              kubernetes:batch/v1:CronJob    update
~   vpc-native-clean-zombie-users-cron                         kubernetes:batch/v1:CronJob    update
~   vpc-native-squad-posts-analytics-refresh-cron              kubernetes:batch/v1:CronJob    update
~   vpc-native-check-analytics-report-cron                     kubernetes:batch/v1:CronJob    update
~   vpc-native-clean-stale-user-transactions-cron              kubernetes:batch/v1:CronJob    update
~   vpc-native-user-posts-analytics-refresh-cron               kubernetes:batch/v1:CronJob    update
~   vpc-native-private-deployment                              kubernetes:apps/v1:Deployment  update
~   vpc-native-clean-zombie-images-cron                        kubernetes:batch/v1:CronJob    update
~   vpc-native-deployment                                      kubernetes:apps/v1:Deployment  update
~   vpc-native-bg-deployment                                   kubernetes:apps/v1:Deployment  update
~   vpc-native-user-profile-analytics-history-clickhouse-cron  kubernetes:batch/v1:CronJob    update
~   vpc-native-clean-zombie-opportunities-cron                 kubernetes:batch/v1:CronJob    update
~   vpc-native-clean-gifted-plus-cron                          kubernetes:batch/v1:CronJob    update
~   vpc-native-update-source-public-threshold-cron             kubernetes:batch/v1:CronJob    update
~   vpc-native-post-analytics-history-day-clickhouse-cron      kubernetes:batch/v1:CronJob    update
~   vpc-native-update-trending-cron                            kubernetes:batch/v1:CronJob    update
~   vpc-native-update-highlighted-views-cron                   kubernetes:batch/v1:CronJob    update
~   vpc-native-materialize-yearly-best-post-archives-cron      kubernetes:batch/v1:CronJob    update
~   vpc-native-daily-digest-cron                               kubernetes:batch/v1:CronJob    update
~   vpc-native-temporal-deployment                             kubernetes:apps/v1:Deployment  update
~   vpc-native-clean-zombie-user-companies-cron                kubernetes:batch/v1:CronJob    update
~   vpc-native-user-profile-updated-sync-cron                  kubernetes:batch/v1:CronJob    update
~   vpc-native-hourly-notification-cron                        kubernetes:batch/v1:CronJob    update
~   vpc-native-expire-super-agent-trial-cron                   kubernetes:batch/v1:CronJob    update
-   vpc-native-api-db-migration-ab4ae3d7                       kubernetes:batch/v1:Job        delete
~   vpc-native-channel-digests-cron                            kubernetes:batch/v1:CronJob    update
... and 11 other changes