no-mistakes(document): Refresh behavior sharding documentation

Author: ruby-dlee

CONTRIBUTING.md

@@ -79,8 +79,8 @@ tmp=$(mktemp -d) && printf 'done: smoke\n' > "$tmp/smoke.status" && FM_STATE_OVE
 Agent Fleet is independently packaged under `tools/agent-fleet` and requires Python 3.11 or newer plus `uv`.
 Run the complete locked verification in [`tools/agent-fleet/RELEASING.md`](tools/agent-fleet/RELEASING.md) before pushing; that document also owns versioning, tagging, and clean-install verification.
 
-Discover tests by listing `tests/*.test.sh`: each is a self-contained bash script named `<subject>.test.sh`, and its header comment describes what it covers, so run one directly to focus on a subject.
-When triaging a red `Behavior tests` job, remember that CI runs that loop under `set -eu` while the local loop above does not: CI stops at the first failing script, so its log proves nothing about the suites that sort after it, and a red job is a lower bound on the failure count rather than the whole list.
+Discover behavior-test entrypoints by listing `tests/*.test.sh` and run one directly to focus on a subject; partition wrappers source their matching `tests/*-suite.sh` implementation.
+When triaging a red behavior shard, use its begin and end markers to identify each failing script: the shard continues through its complete assignment and records every exit code before the final `Behavior tests` job verifies the executed union.
 Reproduce with the exclusion-aware local loop to see every safe failure at once before concluding which ones are real.
 Reproduce in a checkout whose `origin` is the repository's https URL, as CI's own checkout is: the secondmate network-authority fixtures assert that the product pins the resolved address of the origin host, and a checkout whose `origin` is a local filesystem path has no host to pin, so those cases refuse for a reason that exists only locally.
 Run the suites from a checkout sitting on its default branch, not from a task-branch worktree - the worktree-tangle guard fires and several secondmate suites require the default branch, which produces more failures that are pure local artifacts.

docs/configuration.md

@@ -94,7 +94,7 @@ See [`wedge-alarm.md`](wedge-alarm.md) for the channel reference and macOS verif
 The tracked `.no-mistakes.yaml` keeps test evidence outside the repo and defines `commands.test` so no-mistakes runs firstmate's bash behavior suite directly.
 That evidence policy is specific to the firstmate repo: target projects may legitimately commit `.no-mistakes/evidence/` from their own no-mistakes pipeline, but firstmate keeps `.no-mistakes/` local and CI rejects tracked entries under that path.
 That command requires `tmux` on `PATH`, prints `tmux -V`, runs every `tests/*.test.sh` with `bash`, and fails if any script exits non-zero.
-It intentionally mirrors the behavior-test baseline in [`.github/workflows/ci.yml`](../.github/workflows/ci.yml) instead of delegating the test step to an agent.
+It intentionally runs the complete behavior-test inventory serially instead of reproducing the duration-balanced CI sharding owned by [`bin/fm-behavior-shards.sh`](../bin/fm-behavior-shards.sh) or delegating the test step to an agent.
 
 ## Captain preferences (data/captain.md)
 

tests/fm-fleet-sync.test.sh

@@ -139,7 +139,7 @@ build_packed_prunable() {
 
 plant_packed_refs_lock() { : > "$1/.git/packed-refs.lock"; }
 
-# lsof shims mirror tests/fm-teardown.test.sh: no-holder (provably free), a live
+# lsof shims mirror tests/fm-teardown-suite.sh: no-holder (provably free), a live
 # holder, and an lsof error. Written into a per-home fakebin/ prepended to PATH.
 lsof_no_holder() {
   cat > "$1/lsof" <<'SH'

tests/fm-gotmp.test.sh

@@ -7,7 +7,7 @@
 #
 # The fm-spawn side is verified both structurally (the source has the contract lines)
 # and behaviorally (the mkdir + meta-write pattern it uses).
-# Teardown cleanup is covered by tests/fm-teardown.test.sh's full lifecycle fixture.
+# Teardown cleanup is covered by tests/fm-teardown-suite.sh's full lifecycle fixture.
 set -u
 
 ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"