usageAnalytics.ts (924 lines, frozen-baselined) mixes two pure SQL-source
builders with ~20 getXxxRows() query functions. Extract the contiguous,
DB-free builder block verbatim into a leaf, leaving every query function in
the host:
- usageAnalytics/sources.ts (208) AnalyticsParams, BuildUnifiedSourceOptions,
UnifiedSourceResult + buildUnifiedSource + buildPresetUnifiedSource (pure
string builders; no DB, no imports)
Host usageAnalytics.ts: 924 -> 723. The query functions do not call the
builders (callers build the unified source then pass the string in), so the
host re-exports the 5 moved public symbols (2 fns + 3 types) and imports
AnalyticsParams as a type for its query signatures — the public API stays
IDENTICAL (39 symbols). Builder bodies moved byte-identical; the two orphaned
section-header banners that described the moved block were removed with it;
the retained query-function suffix is byte-identical to the original.
Behavior-preserving: 37 existing analytics consumer tests stay green
(usage-analytics 12, usage-endpoint-dimension 3, db-usage-analytics-3500 22);
new tests/unit/db-usageanalytics-split.test.ts (25 assertions) characterizes
buildUnifiedSource's needsAggregated branching (raw-only vs raw+daily_usage_summary)
+ guards the 39-symbol re-export barrel.
Refs #3501.
