PYTHON-5977 APM/logging hot-path optimizations

[NoahStapp]

PYTHON-5977

Changes in this PR

The changes introduced by PYTHON-5903, PYTHON-5846, PYTHON-5745, and PYTHON-5676 caused small but measurable regressions for low-latency, high operation count workloads such as the DSI locust_ping benchmark. Much of this is due to constructing telemetry objects even when APM/logging is disabled and other similar changes that lie on the hot path for such workloads.

This PR attempts to optimize all of those regressions away and return performance to its point before their addition.

Test Plan

Standard test suite, benchmarks.

Results of a simple ping workload benchmark:

Metric	PR	main	main vs PR
Throughput	10,634/s	6,567/s	−38.8%
Mean latency	752 µs	1,219 µs	+62%
p50	~170 µs	~800 µs	~4–5× worse
p99	~5,000 µs	~7,000 µs	+40%

Checklist

Checklist for Author

• [ ] Did you update the changelog (if necessary)?
• [ ] Is there test coverage?
• [ ] Is any followup work tracked in a JIRA ticket? If so, add link(s).

Checklist for Reviewer

• Does the title of the PR reference a JIRA Ticket?
• Do you fully understand the implementation? (Would you be comfortable explaining how this code works to someone else?)
• Is all relevant documentation (README or docstring) updated?

[codecov-commenter]

Codecov Report

❌ Patch coverage is 98.37398% with 2 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
pymongo/_telemetry.py	89.47%	1 Missing and 1 partial ⚠️

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