mosaic thread create|open|read and threads take --tester and run as the tester through
tester-cli.mjs. talk --thread and follow --thread take --tester too, and the row 177 refusal of
--thread with --tester is gone. The bus already checks thread ownership (thread-not-owned), so
the CLI adds no rule of its own, and every verb it sends as the tester is in TESTER_VERBS. follow
already receives with message.receive, so a tester reply arrives without polling inbox.
docs/TOOLS.md and packages/cli/README.md list the new flags.
The new tester-threads.test.mjs runs an in-process Broker. It covers create, list, open, send,
read and follow on a tester thread; thread-not-owned on a human thread both ways; and the human
forms unchanged with no tester transport call. A real-process test runs scripts/mosaic as the
tester. thread-cli.test.mjs and tester-reads.test.mjs drop the argvs that pinned the old
refusal. Brief mutants (talk sent as the human, follow without the thread filter) are killed.
Filbert approved round 1 in #1682 comment 29396 with no findings or notes. Their run on 3da362982,
with row 182 in the broker, added one more mutant (no thread read before the first receive in
follow), and it was killed.