running query with many insert rows is slow to even start

Type: Bug

the query runs quickly but executing the query gets delayed and makes it feel super slow (over a minute)

steps to reproduce:

1. navigate to https://adventofsql.com/challenges/4
2. download the challenge data (see button and instructions at bottom of page)
3. create a local Docker PostgreSQL Server
4. run the downloaded data dump query (advent_of_sql_day_4.sql) via "PGSQL: Execute PostgreSQL Query"
5. note that in the bottom of VS Code it will show "Executing query... 0:SS" and that it will take upwards to a minute or more but once the query runs it only takes ~250ms to actually execute

I can modify the data query using the test data in the same web page and the VS Code extension immediately connects to the DB and runs the query as expected.

My guess is that there is something going on with having a query with 5,000 rows in a single insert statement or that there is some tokenization going on when the VS Code extension communicates with the PostgreSQL server that is being very slow (maybe caused by all of the ARRAY[] usages, some of them are a bit long).

I also tried connected directly to the DB via PSQL CLI tool and running the data dump query there directly via \i ~/Downloads/advent_of_sql_day_4.sql and it runs very quickly without the delay that I see when trying to execute the query via the VS Code extension.

Extension version: 1.8.0
VS Code version: Code 1.103.2 (Universal) (6f17636121051a53c88d3e605c491d22af2ba755, 2025-08-20T16:45:34.255Z)
OS version: Darwin arm64 24.6.0
Modes:

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Start by reproducing the delay with the Advent of SQL challenge 4 dump, Docker PostgreSQL, and the PGSQL: Execute PostgreSQL Query command, then compare it with running the same file through the PSQL CLI. Investigate the extension's handling of the 5,000-row INSERT and ARRAY[] values; done means the extension no longer adds the minute-long startup delay while preserving the fast query execution.