Filters sidebar is timing out

[czephyr]

In #2128 some rollups tables were introduced to be able to use autocomplete.

The filters sidebar are timing out and not loading at all with this warning:

[2026-07-06T17:26:00.757Z][WARN][@clickhouse/client][Config] request_timeout is set to 3600000ms, but send_progress_in_http_headers is not enabled. Long-running queries may fail with socket hang-up errors if they exceed the load balancer idle timeout. Consider enabling progress headers with clickhouse_settings: { send_progress_in_http_headers: 1, http_headers_progress_interval_ms: '<interval>' }. See https://github.com/ClickHouse/clickhouse-js/blob/main/docs/howto/long_running_queries.md for more details.

The filters sidebar is based on these rollup tables:

CREATE TABLE IF NOT EXISTS ${DATABASE}.otel_logs_kv_rollup_15m
(
    `Timestamp` DateTime,
    `ColumnIdentifier` LowCardinality(String),
    `Key` LowCardinality(String),
    `Value` String,
    `count` UInt64,
    INDEX idx_count_minmax count TYPE minmax GRANULARITY 1,
    INDEX idx_timestamp_minmax Timestamp TYPE minmax GRANULARITY 1
)
ENGINE = SummingMergeTree
PARTITION BY toDate(Timestamp)
ORDER BY (ColumnIdentifier, Key, Timestamp, Value)
TTL Timestamp + ${TABLES_TTL}
SETTINGS index_granularity = 8192, ttl_only_drop_parts = 1;

The query ran by HyperDx is not using any of the keys of the table, prompting a full scan of the whole partition.
Even then, slicing on Timestamp would not help a lot, given that its usually ran using the time window of the selection, which can be of multiple days.

SELECT ColumnIdentifier, Key, groupUniqArray(20)(Value) AS Values
FROM logs.otel_logs_kv_rollup_15m
WHERE Value != ''
  AND Timestamp >= toStartOfFifteenMinutes(fromUnixTimestamp64Milli(1783085400000)) AND Timestamp <= toStartOfFifteenMinutes(fromUnixTimestamp64Milli(1783087200000))
GROUP BY ColumnIdentifier, Key
ORDER BY ColumnIdentifier = 'NativeColumn' DESC, ColumnIdentifier = 'ResourceAttributes' DESC, ColumnIdentifier, Key
LIMIT 100

Can this be improved in any way?
Maybe a setting can be added to fix the SELECT params to a subset just for this filters query?