Augment aggregate with variance for CI and add depth experiments

[mIXs222]

Calculate sum and avg CIs for Q1, Q5, Q6, Q8, Q14

• main.rs adds these queries with CI enabled
• cell.rs, count.rs, scaler.rs, agg_accumulator.rs propagate variances for CI
• experiment_ci.sh runs experiment many times
• extract_accuracy_ci.py measures CI accuracy

Add depth experiment scripts and wake query

• script/deep_query_gen.py generate depth-n SQL query
• script/deep_data_gen.py generate multi-column bounded-integer table for deep query experiment
• .../q30.rs wake query that adapts group-by nodes based on depth

Also turning off warning event logs (for tracing experiment, I think?)