* test(e2e): OTEL trace completeness on /chat/completions against a local Jaeger destination
Adds the logging-suite infrastructure for LIT-3787 trace-completeness coverage:
a jaeger service in the compose stack as the OTEL v2 destination (arize_phoenix
preset pointed at it via PHOENIX_COLLECTOR_HTTP_ENDPOINT, so gen-AI spans export
through a preset-owned provider - the code path where trace splits happen), a
typed Jaeger query read-back client, and the first test: one successful
non-streaming /chat/completions call exports ONE complete trace (root SERVER
span + auth/db/cost children + gen-AI CLIENT span, no dangling parents).
* test(e2e): harden the otel trace read-back per review
Jaeger reads now query server-side by the litellm.call_id span tag instead of
paging recent traces and filtering client-side; the compose stack's background
jobs alone can push a request trace past the page. A failed query hard-fails
instead of reading as an empty result, the settle predicate now also waits for
the prefix-matched db span the assertion demands, parent-chain walking follows
CHILD_OF references only, the zero-trace and split-trace failures get distinct
messages, jaeger gets a healthcheck so the depends_on condition is accurate,
and the chat docstring names the route the code actually asserts
* test(e2e): author the chat trace test docstring
* Update logging section in CLAUDE.md
Removed mention of OTEL trace-tree completeness from logging integration section.
