Lifts the atop subprocess machinery into _usage_report_atop.py: running
atop, streaming its parseable output, building/caching the atop_agg C
helper, and reading its TSV. What stays is record parsing, epoch windows
and per-day merging.
Verified by the 100%-coverage tests from the previous commit. An AST
comparison of all 16 functions against HEAD reports 16 identical, 0
mismatches.
_usage_report_render.py imported _run from the parsing module; it now
imports from the module that owns it. That is the same re-export barrel
the last split shipped and had to fix in a follow-up - caught in the same
commit this time. usage_report.py needed no edit at all.
Both modules hold 100% line+branch (94/28 and 130/34, 0 missed). 179
tests before and after; the five new test files collect 8+6+4+14+5 = 37,
which is last commit's 36 plus the one re-homed out of
test_usage_report_modes.py, where it referenced a constant that had
moved out from under it.
The two test files added last commit were themselves over cap (373, 272)
so they are split five ways here - the DropZone lesson from earlier
today, where a lint fix silently added an over-cap file.
Ran the program: a real report from today's logs, through the native
atop_agg path, which is precisely the code this commit moved.
Over-cap 39 -> 38.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_011w2Pj4Ek3ZNMQVYcFHgXDY
