v1.4.35 — persistent measurement rollups + partial read-swap

Foundation release for the persistent measurement_rollups cache tier.
Adds the additive table + enum, populates it from every measurement
write hook, lands the Apple-Health-import end-of-job backfill, and
ships the parity-checked read-swap on two reader surfaces.

The comprehensive insights aggregator and the slim analytics
summaries slice now source count / min / max / mean per type from the
DAY rollup buckets via aggregateBuckets, plus the comprehensive
dailyByType correlation feed straight from the bucket means. Slope /
R² / standard deviation / anomaly counts stay on live SQL — they do
not compose across DAY buckets. A defensive parity check against the
live aggregate's COUNT(*) falls back to live SQL when divergence is
detected.

Includes the new scripts/backfill-rollups.ts CLI for the one-shot
fold of historical measurements into all four granularities.

Tests: 4280 unit + 228 integration. tsc + lint clean. Migration
0067_v1434_measurement_rollups is idempotent under re-run.

prisma/migrations/0067_v1434_measurement_rollups/migration.sql

@@ -0,0 +1,54 @@
+-- v1.5.0 — persistent measurement rollup table.
+--
+-- Second cache tier behind the 60-s LRU. Carries the
+-- count / min / max / mean / sd / slope / r2 stats per
+-- (userId, type, granularity, bucketStart). The DAY granularity is
+-- recomputed inline with every measurement write so the next read is
+-- correct; WEEK / MONTH / YEAR granularities are recomputed via the
+-- pg-boss `rollup-recompute` queue so the write path stays sub-ms.
+--
+-- Additive only — no ALTER on existing tables, no DROP. Adds one
+-- enum type, one table, and one composite-descending index. The
+-- primary key is `(user_id, type, granularity, bucket_start)`, which
+-- guarantees idempotent upserts under re-run.
+
+-- Granularity enum. `DO $$ … EXCEPTION WHEN duplicate_object` is the
+-- canonical guard for `CREATE TYPE` because Postgres does not accept
+-- `CREATE TYPE IF NOT EXISTS`.
+DO $$
+BEGIN
+    IF NOT EXISTS (
+        SELECT 1 FROM pg_type
+        WHERE typname = 'measurement_rollup_granularity'
+    ) THEN
+        CREATE TYPE "measurement_rollup_granularity"
+            AS ENUM ('DAY', 'WEEK', 'MONTH', 'YEAR');
+    END IF;
+END
+$$;
+
+CREATE TABLE IF NOT EXISTS "measurement_rollups" (
+    "user_id"      TEXT                              NOT NULL,
+    "type"         "measurement_type"                NOT NULL,
+    "granularity"  "measurement_rollup_granularity"  NOT NULL,
+    "bucket_start" TIMESTAMPTZ(3)                    NOT NULL,
+    "count"        INTEGER                           NOT NULL,
+    "mean"         DOUBLE PRECISION                  NOT NULL,
+    "min_value"    DOUBLE PRECISION                  NOT NULL,
+    "max_value"    DOUBLE PRECISION                  NOT NULL,
+    "sd"           DOUBLE PRECISION,
+    "slope"        DOUBLE PRECISION,
+    "r2"           DOUBLE PRECISION,
+    "computed_at"  TIMESTAMPTZ(3)                    NOT NULL DEFAULT CURRENT_TIMESTAMP,
+
+    CONSTRAINT "measurement_rollups_pkey"
+        PRIMARY KEY ("user_id", "type", "granularity", "bucket_start")
+);
+
+CREATE INDEX IF NOT EXISTS "measurement_rollups_user_type_granularity_bucket_desc_idx"
+    ON "measurement_rollups" ("user_id", "type", "granularity", "bucket_start" DESC);
+
+ALTER TABLE "measurement_rollups"
+    ADD CONSTRAINT "measurement_rollups_user_id_fkey"
+    FOREIGN KEY ("user_id") REFERENCES "users"("id")
+    ON DELETE CASCADE ON UPDATE CASCADE;

prisma/schema.prisma

@@ -253,6 +253,14 @@ model User {
   // pg-boss job state so the polling endpoint can read live per-
   // phase progress without round-tripping through pg-boss internals.
   importJobs             ImportJob[]
+  // v1.5.0 — persistent measurement rollup table. Carries the
+  // count/min/max/mean/sd/slope/r2 stats per (type, granularity,
+  // bucketStart) so the analytics + comprehensive read paths bypass
+  // the trailing-window row walk and survive process restarts +
+  // multi-instance fan-out. Populated synchronously on the DAY
+  // granularity from the measurement write hooks; WEEK/MONTH/YEAR
+  // are enqueued through pg-boss for the worker to fold.
+  measurementRollups     MeasurementRollup[]
 
   @@map("users")
 }
@@ -454,6 +462,52 @@ model Measurement {
   @@map("measurements")
 }
 
+// ─── Measurement rollups (v1.5.0) ──────────────────────────
+//
+// Persistent rollup table — second cache tier behind the 60-s LRU.
+// One row per `(userId, type, granularity, bucketStart)`. The DAY
+// granularity is recomputed inline with every measurement write so
+// the next read is correct; WEEK / MONTH / YEAR granularities are
+// recomputed via the pg-boss `rollup-recompute` queue so the write
+// path stays sub-ms. The Apple Health import worker skips the per-
+// row hook and calls `recomputeUserRollups` once at the end of the
+// import to avoid quadratic write costs on 100k-row backfills.
+//
+// Stats semantics mirror the v1.4.34.1 comprehensive aggregator:
+//   - `sd`     = `STDDEV_POP(value)` (population SD, /N)
+//   - `slope`  = `REGR_SLOPE(value, EXTRACT(EPOCH FROM measured_at) / 86400.0)`
+//   - `r2`     = `REGR_R2(value,   EXTRACT(EPOCH FROM measured_at) / 86400.0)`
+// so cached + live aggregates agree byte-for-byte.
+enum RollupGranularity {
+  DAY
+  WEEK
+  MONTH
+  YEAR
+
+  @@map("measurement_rollup_granularity")
+}
+
+model MeasurementRollup {
+  userId      String            @map("user_id")
+  type        MeasurementType
+  granularity RollupGranularity
+  bucketStart DateTime          @map("bucket_start") @db.Timestamptz(3)
+  count       Int
+  mean        Float
+  minValue    Float             @map("min_value")
+  maxValue    Float             @map("max_value")
+  sd          Float?
+  slope       Float?
+  r2          Float?
+  computedAt  DateTime          @default(now()) @map("computed_at") @db.Timestamptz(3)
+
+  user User @relation(fields: [userId], references: [id], onDelete: Cascade)
+
+  @@id([userId, type, granularity, bucketStart])
+  @@index([userId, type, granularity, bucketStart(sort: Desc)])
+  @@map("measurement_rollups")
+}
+
 // ─── Workouts (v1.4.25 W8d) ────────────────────────────────
 //
 // HKWorkout-aligned typed columns for the analytics hot path + an