feat(profiling): `thread id` label on every sample

[realFlowControl]

Description

Turns out the profiling-backend assumes that all pprof based profiles emit a thread id and thread name label with every sample, so this PR aims to do this. Edit: profiling-backend was updated to not require the thread name, but we should add at least thread id anyway. Since thread names are uncommon (we don't know of a single PHP program/library which names threads), we omit thread name for now.

Took this as an opportunity to clean up a few things:

• message_labels was renamed to common_labels and now sets the "fiber" tag (was in prepare_message before). It also accepts a parameter for how much extra space to allocate in the Vec, so callers can avoid reallocations.
• Avoided lazy_static labels, and removed un-necessary vec! usages to reduce allocations.
• We always call send_message(prepare_message(...)), so I made a helper for this called prepare_and_send_message.

PROF-9887

Reviewer checklist

• [ ] Test coverage seems ok.
• [x] Appropriate labels assigned.

[pr-commenter[bot]]

Benchmarks

Benchmark execution time: 2024-06-10 11:38:05

Comparing candidate commit 9e04353bc99a9baa3077645f8adca48317b11a37 in PR branch florian/thread-name-id with baseline commit e63625078edc52eb92e4c6104f0daaab3ec8fa63 in branch master.

Found 0 performance improvements and 0 performance regressions! Performance is the same for 27 metrics, 9 unstable metrics.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 79.32%. Comparing base (e636250) to head (be0af97). Report is 2 commits behind head on master.

Additional details and impacted files

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[realFlowControl]

@morrisonlevi I can not approve but I approve