Persist the in-process counters by adding them into the cumulative
on-disk file, then reset the process counters. The counters live in the
MCP/CLI process — the dashboard is a separate process and can only see
them through this file (#505).
The outline view for a large file: the symbol list with line spans, or the
key structure of a data/prose format. A file with no extractable structure
gets the header (line count) and a pointer to lines:N-M.
Owner rule for a read that names no range (no mode, or auto): a file
with more than OUTLINE_MIN_LINES lines comes as its outline, a smaller
file comes whole. A pure function of the resolution, the path and the line
count, so the delivered view stays byte-stable (#498).