chore: clear v1.11.2 QA-low cleanups

- Drop the unused `now` field from the coach `ExtractOpts` type; fact
  extraction never read it (conversation-summary keeps its own `now`).
- Correct the no-ladder tiebreak docstring in measurement-read: the
  collapse picks the alphabetically smallest source name, matching the
  live-SQL `ORDER BY … source` tiebreak, not max count.
- Replace the hand-inlined canonical-source subquery in the summaries
  rollup-path narrows query with `canonicalMeasurementsFrom(rank, "90 days")`
  for live/rollup parity with its siblings.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/lib/ai/coach/facts.ts

@@ -58,7 +58,6 @@ type RunCompletionFn = typeof runStatusCompletion;
 type PrismaLike = Pick<typeof prisma, "coachFact" | "coachConversation">;
 
 interface ExtractOpts {
-  now?: Date;
   runCompletion?: RunCompletionFn;
   prisma?: PrismaLike;
   locale?: string;

src/lib/analytics/summaries-slice.ts

@@ -348,27 +348,7 @@ async function computeFromRollups(userId: string): Promise<SummariesSlice> {
         ) FILTER (
           WHERE m."measured_at" >= NOW() - INTERVAL '90 days'
         )::double precision                                           AS r2_90
-      FROM (
-        SELECT mm.*
-        FROM measurements mm
-        JOIN (
-          SELECT DISTINCT ON ("type", date_trunc('day', "measured_at"))
-            "type"                              AS t,
-            date_trunc('day', "measured_at")    AS d,
-            "source"                            AS canon
-          FROM measurements
-          WHERE "user_id" = $1
-            AND "deleted_at" IS NULL
-            AND "measured_at" >= NOW() - INTERVAL '90 days'
-          ORDER BY "type", date_trunc('day', "measured_at"), (${rankUnqualified}), "source"
-        ) c
-          ON c.t = mm."type"
-          AND c.d = date_trunc('day', mm."measured_at")
-          AND c.canon = mm."source"
-        WHERE mm."user_id" = $1
-          AND mm."deleted_at" IS NULL
-          AND mm."measured_at" >= NOW() - INTERVAL '90 days'
-      ) m
+      FROM ${canonicalMeasurementsFrom(rankUnqualified, "90 days")}
       GROUP BY m."type"
     `,
       userId,

src/lib/rollups/measurement-read.ts

@@ -73,8 +73,9 @@ export interface SourcedBucketRow {
  * Resolution per bucket:
  *   1. the first source in the metric's ladder that is present → canonical;
  *   2. no ladder match (an unlisted source, or a type with no ladder) → the
- *      row with the most readings (max `count`), tie-broken by source name,
- *      so the bucket neither doubles nor goes dark.
+ *      row with the alphabetically smallest source name, so the bucket
+ *      neither doubles nor goes dark AND the pick matches the live-SQL
+ *      paths' `ORDER BY … source` tiebreak.
  *
  * Input order is preserved (buckets emit in first-seen order). A single-source
  * day (the common case) short-circuits to the row unchanged.