proxy: add more http logging

[conradludgate]

Problem

hard to see where time is taken during HTTP flow.

Summary of changes

add a lot more for query state. add a conn_id field to the sql-over-http span

Checklist before requesting a review

• I have performed a self-review of my code.
• If it is a core feature, I have added thorough tests.
• Do we need to implement analytics? if so did you add the relevant metrics to the dashboard?
• If this PR requires public announcement, mark it with /release-notes label and add several sentences in this section.

Checklist before merging

• Do not forget to reformat commit message to not include the above checklist

[github-actions]

2430 tests run: 2320 passed, 0 failed, 110 skipped (full report)

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Flaky tests (4)

Postgres 16

• test_compute_pageserver_connection_stress: debug
• test_secondary_mode_eviction: release

Postgres 15

• test_crafted_wal_end[last_wal_record_crossing_segment]: debug

Postgres 14

• test_sharding_split_smoke: release

Code coverage (full report)

• functions: 54.9% (11880 of 21625 functions)
• lines: 82.1% (66281 of 80693 lines)

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_{The comment gets automatically updated with the latest test results
bd6c68e at 2024-02-12T15:01:09.339Z :recycle:}