feat(seer): Scope night shift result dedupe to (run, kind, idempotency_key)

[trevor-e]

Description

Stacked on #118976, which added a code-level recorded-rows check so redelivered shard results neither re-trigger autofix nor write duplicate result rows. This PR adds the DB backstop for the one residual race — two deliveries of the same shard processed concurrently, both passing the check before either writes.

Originally scoped to (run, group), but night shift is meant to support workflows beyond group-based triage, so results need a dedupe key that isn't always a group. Generalized to an idempotency_key field, unique per (run, kind):

• Migration 0026 adds the idempotency_key column and a partial unique constraint on (run, kind, idempotency_key) WHERE idempotency_key IS NOT NULL (created CONCURRENTLY by the migration framework).

Rows written before this deploys keep idempotency_key = NULL — they're excluded from the constraint by its partial condition, so no backfill is needed. They'll never be redelivered at this point, so there's nothing to protect; leaving them null also keeps any past duplicates queryable for investigation.

delivery.py now sets idempotency_key = str(group_id) for triage results and checks it (instead of raw group_id) for redelivery dedupe. It already used bulk_create(..., ignore_conflicts=True), a no-op until the constraint exists.

Merge sequencing: land after #118976 has fully deployed. That way the recorded-rows check is live while the index build runs, minimizing the window where a fresh duplicate could fail the concurrent index creation.

[sentry]

Sentry Snapshot Testing

Name	Added	Removed	Changed	Renamed	Unchanged	Skipped	Status
sentry-frontend sentry-frontend	0	0	0	0	451	0	✅ Unchanged

⚙️ sentry-frontend Snapshot Settings

[github-actions]

This PR has a migration; here is the generated SQL for src/sentry/seer/migrations/0026_dedupe_night_shift_run_results.py src/sentry/seer/migrations/0027_unique_night_shift_result_run_group.py

for 0026_dedupe_night_shift_run_results in seer

--
-- Raw Python operation
--
-- THIS OPERATION CANNOT BE WRITTEN AS SQL

for 0027_unique_night_shift_result_run_group in seer

--
-- Create constraint seer_nightshiftrunresult_unique_run_group on model seernightshiftrunresult
--
CREATE UNIQUE INDEX CONCURRENTLY "seer_nightshiftrunresult_unique_run_group" ON "seer_nightshiftrunissue" ("run_id", "group_id") WHERE "group_id" IS NOT NULL;

[github-actions]

This PR has a migration; here is the generated SQL for src/sentry/seer/migrations/0026_add_night_shift_result_idempotency_key.py src/sentry/seer/migrations/0027_backfill_night_shift_result_idempotency_key.py src/sentry/seer/migrations/0028_unique_night_shift_result_run_kind_idempotency_key.py

for 0026_add_night_shift_result_idempotency_key in seer

--
-- Add field idempotency_key to seernightshiftrunresult
--
ALTER TABLE "seer_nightshiftrunissue" ADD COLUMN "idempotency_key" varchar(256) NULL;

for 0027_backfill_night_shift_result_idempotency_key in seer

--
-- Raw Python operation
--
-- THIS OPERATION CANNOT BE WRITTEN AS SQL

for 0028_unique_night_shift_result_run_kind_idempotency_key in seer

--
-- Create constraint seer_nightshiftrunresult_unique_run_kind_idempotency_key on model seernightshiftrunresult
--
CREATE UNIQUE INDEX CONCURRENTLY "seer_nightshiftrunresult_unique_run_kind_idempotency_key" ON "seer_nightshiftrunissue" ("run_id", "kind", "idempotency_key") WHERE "idempotency_key" IS NOT NULL;

[cursor]

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

^{❌ Bugbot Autofix is OFF. To automatically fix reported issues with cloud agents, enable autofix in the Cursor dashboard.}

^{Reviewed by Cursor Bugbot for commit afc1266. Configure here.}

[github-actions]

This PR has a migration; here is the generated SQL for src/sentry/seer/migrations/0026_add_night_shift_result_idempotency_key.py src/sentry/seer/migrations/0027_unique_night_shift_result_run_kind_idempotency_key.py

for 0026_add_night_shift_result_idempotency_key in seer

--
-- Add field idempotency_key to seernightshiftrunresult
--
ALTER TABLE "seer_nightshiftrunissue" ADD COLUMN "idempotency_key" varchar(256) NULL;

for 0027_unique_night_shift_result_run_kind_idempotency_key in seer

--
-- Create constraint seer_nightshiftrunresult_unique_run_kind_idempotency_key on model seernightshiftrunresult
--
CREATE UNIQUE INDEX CONCURRENTLY "seer_nightshiftrunresult_unique_run_kind_idempotency_key" ON "seer_nightshiftrunissue" ("run_id", "kind", "idempotency_key") WHERE "idempotency_key" IS NOT NULL;

[github-actions]

This PR has a migration; here is the generated SQL for src/sentry/seer/migrations/0026_add_night_shift_result_idempotency_key.py

for 0026_add_night_shift_result_idempotency_key in seer

--
-- Add field idempotency_key to seernightshiftrunresult
--
ALTER TABLE "seer_nightshiftrunissue" ADD COLUMN "idempotency_key" varchar(256) NULL;
--
-- Create constraint seer_nightshiftrunresult_unique_run_kind_idempotency_key on model seernightshiftrunresult
--
CREATE UNIQUE INDEX CONCURRENTLY "seer_nightshiftrunresult_unique_run_kind_idempotency_key" ON "seer_nightshiftrunissue" ("run_id", "kind", "idempotency_key") WHERE "idempotency_key" IS NOT NULL;

[trevor-e]

@sentry review