perf: Merge Precision in-place

[AdamGS]

Which issue does this PR close?

Follow up of #20768.

Rationale for this change

Precision::min/max allocates a lot of new ScalarValues, and it can be done in place.
While running the sql_planner benchmark, it seems like for clickbench Statistics::try_merge_iter is a significant part of the runtime, and this PR improves that part by about 20-25% locally.

What changes are included in this PR?

Introduces a couple of of new internal functions to calculate the min/max of a Precision in-place.

Are these changes tested?

Existing general tests, and a few new unit tests.

Are there any user-facing changes?

None

[AdamGS]

Locally, the perf impact on the stats_merge benchmark are:

stats_merge/try_merge_iter/10parts_1cols
                        time:   [261.85 ns 263.02 ns 264.27 ns]
                        change: [−20.578% −20.212% −19.831%] (p = 0.00 < 0.05)
                        Performance has improved.
Benchmarking stats_merge/try_merge_iter/10parts_5cols: Collecting 100 samples in estimatedstats_merge/try_merge_iter/10parts_5cols
                        time:   [1.1278 µs 1.1310 µs 1.1346 µs]
                        change: [−18.151% −17.782% −17.421%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 9 outliers among 100 measurements (9.00%)
  3 (3.00%) high mild
  6 (6.00%) high severe
Benchmarking stats_merge/try_merge_iter/10parts_20cols: Collecting 100 samples in estimatestats_merge/try_merge_iter/10parts_20cols
                        time:   [4.1735 µs 4.1785 µs 4.1843 µs]
                        change: [−18.384% −18.204% −18.034%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 8 outliers among 100 measurements (8.00%)
  3 (3.00%) high mild
  5 (5.00%) high severe
Benchmarking stats_merge/try_merge_iter/100parts_1cols: Collecting 100 samples in estimatestats_merge/try_merge_iter/100parts_1cols
                        time:   [2.2418 µs 2.2478 µs 2.2547 µs]
                        change: [−22.768% −22.464% −22.154%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 10 outliers among 100 measurements (10.00%)
  6 (6.00%) high mild
  4 (4.00%) high severe
Benchmarking stats_merge/try_merge_iter/100parts_5cols: Collecting 100 samples in estimatestats_merge/try_merge_iter/100parts_5cols
                        time:   [11.596 µs 11.628 µs 11.665 µs]
                        change: [−14.560% −14.268% −13.925%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 2 outliers among 100 measurements (2.00%)
  1 (1.00%) high mild
  1 (1.00%) high severe
Benchmarking stats_merge/try_merge_iter/100parts_20cols: Collecting 100 samples in estimatstats_merge/try_merge_iter/100parts_20cols
                        time:   [43.707 µs 43.818 µs 43.949 µs]
                        change: [−16.318% −16.016% −15.691%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 3 outliers among 100 measurements (3.00%)
  1 (1.00%) high mild
  2 (2.00%) high severe
Benchmarking stats_merge/try_merge_iter/500parts_1cols: Collecting 100 samples in estimatestats_merge/try_merge_iter/500parts_1cols
                        time:   [11.530 µs 11.559 µs 11.591 µs]
                        change: [−23.035% −22.749% −22.473%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 6 outliers among 100 measurements (6.00%)
  5 (5.00%) high mild
  1 (1.00%) high severe
Benchmarking stats_merge/try_merge_iter/500parts_5cols: Collecting 100 samples in estimatestats_merge/try_merge_iter/500parts_5cols
                        time:   [57.852 µs 58.011 µs 58.178 µs]
                        change: [−15.960% −15.588% −15.191%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 7 outliers among 100 measurements (7.00%)
  5 (5.00%) high mild
  2 (2.00%) high severe
Benchmarking stats_merge/try_merge_iter/500parts_20cols: Collecting 100 samples in estimatstats_merge/try_merge_iter/500parts_20cols
                        time:   [220.48 µs 221.23 µs 222.16 µs]
                        change: [−13.692% −13.092% −12.313%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 3 outliers among 100 measurements (3.00%)
  1 (1.00%) high mild
  2 (2.00%) high severe