feat(api): return TOO_MANY_BYTES as clickhouse error instead of rate limit

Stop converting ClickHouse TOO_MANY_BYTES (code 307) errors into
RateLimitExceeded. This lets consumers (e.g. sentry) distinguish
"query scanned too many bytes" from snuba-level rate limiting.

- Remove RateLimitExceeded conversion for TOO_MANY_BYTES in db_query.py
- Add TOO_MANY_BYTES to ACCEPTABLE_CLICKHOUSE_ERROR_CODES (returns 400)
- Update test to assert clickhouse error type with code 307

Co-Authored-By: Claude <noreply@anthropic.com>

Author: cvxluo

snuba/web/constants.py

@@ -16,6 +16,8 @@
     *CLICKHOUSE_TYPING_ERROR_CODES,
     # queries that can never return the amount of data requested by the user are not an internal error
     ErrorCodes.MEMORY_LIMIT_EXCEEDED,
+    # query exceeded the max_bytes_to_read limit set by an allocation policy
+    ErrorCodes.TOO_MANY_BYTES,
 }
 
 NON_RETRYABLE_CLICKHOUSE_ERROR_CODES = {

snuba/web/db_query.py

@@ -476,12 +476,6 @@ def _raw_query(
         elif isinstance(cause, ClickhouseError):
             error_code = cause.code
             status = get_query_status_from_error_codes(error_code)
-            if error_code == ErrorCodes.TOO_MANY_BYTES:
-                calculated_cause = RateLimitExceeded(
-                    "Query scanned more than the allocated amount of bytes",
-                    quota_allowance=stats["quota_allowance"],
-                )
-
             with configure_scope() as scope:
                 fingerprint = ["{{default}}", str(cause.code), dataset_name]
                 if error_code not in constants.CLICKHOUSE_SYSTEMATIC_FAILURES:

tests/test_snql_api.py

@@ -1329,15 +1329,10 @@ def test_allocation_policy_max_bytes_to_read(self) -> None:
                     }
                 ),
             )
-            # TOO_MANY_BYTES is a clickhouse error, not a rate limit.
-            # The response should surface the clickhouse error type and code
-            # so that consumers (e.g. sentry) can distinguish it from
-            # snuba-level rate limiting.
             assert response.status_code == 400
             assert response.json["error"]["type"] == "clickhouse"
             assert response.json["error"]["code"] == 307
 
-            # quota_allowance should still be available in stats
             expected_quota_allowance = {
                 "details": {
                     "MaxBytesPolicy123": {