`rollupLambda` with `unionWithSourceData` always queries the source, even when the requested date range is entirely historical

**Describe the bug**
When a `rollupLambda` pre-aggregation uses `unionWithSourceData: true`, Cube issues a live query against the source on every request, including when the requested date range lies entirely within already-built rollup partitions. The live query is lower-bounded by the end of the last matched partition and has no upper bound, so it aggregates every row after that point - all of which are discarded by the outer query.

**To Reproduce**
see repro (Postgres + Cube 1.7.28, `docker compose up -d`).

**Expected behavior**
Either skip the source query when `matchedTimeDimensionDateRange` does not overlap `]buildRangeEnd, ∞[`, or bound the live query by the requested range.

**Minimally reproducible Cube Schema**

```javascript
cube(`Events`, {
sql: `SELECT * FROM public.events`,

preAggregations: {
eventsLambda: {
type: `rollupLambda`,
unionWithSourceData: true,
rollups: [Events.eventsRollup],
},

eventsRollup: {
type: `rollup`,
measures: [Events.count],
timeDimension: Events.ts,
granularity: `day`,
partitionGranularity: `month`,
external: true,
scheduledRefresh: false,
buildRangeStart: { sql: `SELECT DATE '2024-01-01'` },
buildRangeEnd: { sql: `SELECT CURRENT_DATE` },
},
},

measures: {
count: { type: `count` },
},

dimensions: {
id: { sql: `id`, type: `number`, primaryKey: true },
status: { sql: `status`, type: `string` },
ts: { sql: `ts`, type: `time` },
},
});
```

```yaml
services:
postgres:
image: postgres:16
environment:
POSTGRES_USER: cube
POSTGRES_PASSWORD: cube
POSTGRES_DB: repro
ports:
- 5433:5432
volumes:
- ./init:/docker-entrypoint-initdb.d
healthcheck:
test: ["CMD-SHELL", "pg_isready -U cube -d repro"]
interval: 3s
timeout: 3s
retries: 20

cube:
image: cubejs/cube:v1.7.28
depends_on:
postgres:
condition: service_healthy
ports:
- 4001:4000
environment:
CUBEJS_DEV_MODE: "true"
CUBEJS_LOG_LEVEL: info
CUBEJS_DB_TYPE: postgres
CUBEJS_DB_HOST: postgres
CUBEJS_DB_PORT: 5432
CUBEJS_DB_NAME: repro
CUBEJS_DB_USER: cube
CUBEJS_DB_PASS: cube
CUBEJS_API_SECRET: repro-secret
volumes:
- ./cube.js:/cube/conf/cube.js
- ./model:/cube/conf/model
- cubestore:/cube/conf/.cubestore

volumes:
cubestore:
```

```sql
CREATE TABLE events (
id serial PRIMARY KEY,
ts timestamp NOT NULL,
status text NOT NULL
);

-- Faible volume sur le mois qui sera interrogé (fevrier 2024) : 696 lignes.
INSERT INTO events (ts, status)
SELECT g, 'queried'
FROM generate_series(timestamp '2024-02-01', timestamp '2024-02-29 23:00', interval '1 hour') g;

-- Fort volume APRES le mois interroge : ~1.3M lignes.
-- Aucune de ces lignes ne peut contribuer au resultat d'une requete sur fevrier 2024.
INSERT INTO events (ts, status)
SELECT g, 'noise'
FROM generate_series(timestamp '2024-03-01', timestamp '2026-08-01', interval '1 minute') g;

CREATE INDEX ON events (ts);
```

**Results**

With the request :
```json
{
"measures": ["Events.count"],
"timeDimensions": [
{
"dimension": "Events.ts",
"dateRange": ["2024-02-01", "2024-02-29"]
}
]
}
```

| | With `rollupLambda` | Without|
|---|---|---|
| Mesure 1 | 286 ms | 50 ms |
| Mesure 2 | 252 ms | 29 ms |
| Mesure 3 | 244 ms | 30 ms |
| Mesure 4 | 251 ms | 29 ms |
| **Médiane** | **~251 ms** | **~29 ms** |
| Requêtes live vers Postgres | 5 | **0** |
| Résultat | 696 | 696 |

**Version:**
1.7.28 (behaviour identical on master, 1.7.29)

**Additional context**

Issue created with the help of AI for both the writing and the repro steps