feat(contributions): global milestones

[idoshamun]

Adds DB-driven global milestones for the giveback launch. Pull-only (no broadcast) — the client polls the last reached milestone for the header gift-icon animation.

What's included

• ContributionMilestone entity (value unique / title / active / sortOrder / reachedAt) + migration.
• Detection on the approved-submission event (api.v1.contribution-action-completed): sum lifetime approved points, idempotently stamp any crossed milestones (UPDATE ... WHERE value <= :total AND reachedAt IS NULL), refresh the poll cache. Low-frequency event, so no counter/cron and no drift.
• contributionLastReachedMilestone query — the single high-frequency poll, served from a tiny Redis cache (contribution:last-milestone, 60s TTL), deliberately kept out of the heavy contributionStatus aggregates.
• Private admin CRUD for milestones (POST/PATCH/DELETE /contributions/milestones).

Notes

• Milestone metric = total approved points, lifetime. Thresholds are admin-managed, not hardcoded.
• Generated migration was cleaned to only the table + 2 indexes (IF NOT EXISTS, no CONCURRENTLY).

First of 3 PRs for the giveback launch (next: first-1k founding award; leaderboard + causes breakdown).

[pulumi]

🍹 The Update (preview) for dailydotdev/api/prod (at cb63883) was successful.

Resource Changes

    Name                                                       Type                                  Operation
~   vpc-native-update-tags-str-cron                            kubernetes:batch/v1:CronJob           update
~   vpc-native-materialize-yearly-best-post-archives-cron      kubernetes:batch/v1:CronJob           update
~   vpc-native-user-posts-analytics-refresh-cron               kubernetes:batch/v1:CronJob           update
~   vpc-native-calculate-top-readers-cron                      kubernetes:batch/v1:CronJob           update
~   vpc-native-user-profile-updated-sync-cron                  kubernetes:batch/v1:CronJob           update
~   vpc-native-clean-zombie-users-cron                         kubernetes:batch/v1:CronJob           update
~   vpc-native-channel-digests-cron                            kubernetes:batch/v1:CronJob           update
~   vpc-native-rotate-weekly-quests-cron                       kubernetes:batch/v1:CronJob           update
~   vpc-native-check-analytics-report-cron                     kubernetes:batch/v1:CronJob           update
~   vpc-native-update-source-public-threshold-cron             kubernetes:batch/v1:CronJob           update
~   vpc-native-ws-deployment                                   kubernetes:apps/v1:Deployment         update
~   vpc-native-update-tag-materialized-views-cron              kubernetes:batch/v1:CronJob           update
~   vpc-native-validate-active-users-cron                      kubernetes:batch/v1:CronJob           update
~   vpc-native-hourly-notification-cron                        kubernetes:batch/v1:CronJob           update
~   vpc-native-post-analytics-clickhouse-cron                  kubernetes:batch/v1:CronJob           update
~   vpc-native-clean-old-notifications-cron                    kubernetes:batch/v1:CronJob           update
~   vpc-native-deployment                                      kubernetes:apps/v1:Deployment         update
~   vpc-native-clean-zombie-images-cron                        kubernetes:batch/v1:CronJob           update
+   api-sub-api.contribution-action-completed-milestone        gcp:pubsub/subscription:Subscription  create
~   vpc-native-user-profile-analytics-history-clickhouse-cron  kubernetes:batch/v1:CronJob           update
~   vpc-native-generic-referral-reminder-cron                  kubernetes:batch/v1:CronJob           update
~   vpc-native-clean-expired-better-auth-sessions-cron         kubernetes:batch/v1:CronJob           update
~   vpc-native-expire-super-agent-trial-cron                   kubernetes:batch/v1:CronJob           update
-   vpc-native-api-clickhouse-migration-758c8751               kubernetes:batch/v1:Job               delete
~   vpc-native-channel-highlights-cron                         kubernetes:batch/v1:CronJob           update
~   vpc-native-worker-job-deployment                           kubernetes:apps/v1:Deployment         update
~   vpc-native-temporal-deployment                             kubernetes:apps/v1:Deployment         update
~   vpc-native-post-lifecycle-state-clickhouse-cron            kubernetes:batch/v1:CronJob           update
~   vpc-native-post-analytics-achievements-cron                kubernetes:batch/v1:CronJob           update
~   vpc-native-private-deployment                              kubernetes:apps/v1:Deployment         update
+   vpc-native-api-clickhouse-migration-c1b31b6a               kubernetes:batch/v1:Job               create
~   vpc-native-rotate-daily-quests-cron                        kubernetes:batch/v1:CronJob           update
~   vpc-native-update-trending-cron                            kubernetes:batch/v1:CronJob           update
~   vpc-native-subscription-anniversary-achievements-cron      kubernetes:batch/v1:CronJob           update
~   vpc-native-update-views-cron                               kubernetes:batch/v1:CronJob           update
~   vpc-native-clean-zombie-user-companies-cron                kubernetes:batch/v1:CronJob           update
~   vpc-native-update-current-streak-cron                      kubernetes:batch/v1:CronJob           update
~   vpc-native-materialize-monthly-best-post-archives-cron     kubernetes:batch/v1:CronJob           update
~   vpc-native-clean-channel-highlights-cron                   kubernetes:batch/v1:CronJob           update
~   vpc-native-clean-stale-user-transactions-cron              kubernetes:batch/v1:CronJob           update
~   vpc-native-daily-digest-cron                               kubernetes:batch/v1:CronJob           update
... and 16 other changes