What

This PR consolidates the remaining logger usage onto shared Log.* categories and trims noisy logging across the transcription stack.

Why

This is the first PR in a 2-PR stack.

It conceptually sits on top of yazinsai/OpenOats#232, but that upstream PR is still open. To keep the diff reviewable now, this fork uses stack/pr232-base as a temporary mirror of the #232 tip and targets this PR there.

The tradeoff is one temporary base branch in the fork. The benefit is a mechanical cleanup PR that stays separate from the behavioral transcription fixes.

How

• adds the missing shared logger categories in Utils/Logging.swift
• replaces remaining file-local Logger(...) instances with Log.*
• removes duplicate subsystem/category declarations
• reduces low-signal logging noise without changing runtime behavior
• preserves the explicit diarization finalize error logging path

Testing

• swift test
• Result: 310 tests passed, 0 failures

Migration / rollback

No migration.

If any part of this cleanup turns out to be undesirable, it can be reverted as a single squashed commit.

Stack

• Base: stack/pr232-base (temporary mirror of the current #232 tip in this fork)
• Follow-up stacked PR: stack/transcription-fix