remote_tools: item class by mask instead of is_code/is_data calls

The listing walk asked ida_bytes.is_code/is_data ~6 times per head (the row's
kind, plus twice more via _is_unknown_f from _advance and _rows_for). Each is
a python wrapper around a C call; the mask compare is the same question with
no call at all.

Equivalence was proven, not assumed: checked against is_code/is_data over all
four classes x 16,020 synthetic flag values, and over every distinct flag in
a real database (125 across 207,191 heads). Zero mismatches. Output is
byte-identical over 3003 rows spanning all five row kinds.

(The digest DOES differ run to run, which looked alarming until it turned out
the same unmodified code differs too: hash() is seed-randomised per process
and the digest is documented as per-process. Cross-process digest comparison
proves nothing.)

Worth 5.6% on a skeleton page (3.37 -> 3.18ms) and 2.7% on a full one -- the
~5% the profile predicted, not the 1.5-2x I guessed out loud. End to end it
does NOT move bash's boot (3117 -> 3140ms, noise), because at 455 x 3.18ms
the backend is now only ~1.45s of a 3.14s boot: the other ~54% is transport,
Head construction and model bookkeeping on the client.

Only the two hot sites changed. The four in the operand-format paths are not
per-head and read better as is_code/is_data.

Full gate: 1050 passed.

0 files changed, 0 insertions, 0 deletions