chore(agent): commit the machine tier and the doctrine text the checkout was already running

Landing blocker for #61 and #63: the deployment checkout is 12 commits behind and
`merge --ff-only` refuses while tracked paths are dirty. Discard is not available here
(workspace policy: no `checkout`/`stash` on shared state), so the dirt is committed.

- `agent/APPEND_SYSTEM.md`: the point-of-use / one-work-log / PR-link doctrine, already
  byte-identical to `origin/main` (`cmp` against the trunk blob: no difference). No new
  prose — the commit exists so the trunk merge can proceed.
- `agent/config.yml` and `agent/managed-skills/**`: the machine-live tier the heartbeat
  owns (AGENTS.md § Live-sync tiers).

`ALLOW_SECRETS=1` was used, deliberately and after auditing the staged diff by hand: the
only credential-shaped strings in it are two copies of `AKIA0000000000000EXAMPLE` — the
inert all-zero AWS example id — and they appear inside the two skill pages that teach
that exact placeholder shape. This checkout is still running the pre-#61 hook; the merged
gate (value-scoped placeholder filter, `71601f7`) exempts this value, so the refusal
dies with this landing. No `--no-verify` was used: the gate ran and its verdict is
recorded here.

Refs #61

agent/managed-skills/bats-output-glob-red-proof-traps/SKILL.md

@@ -0,0 +1,51 @@
+---
+name: bats-output-glob-red-proof-traps
+description: "Write red bats tests over command output: [[ ]] glob adjacency (quoted * is literal), run-capture vs test stdout in failure dumps, and proving red against pre-fix code before trusting green."
+---
+
+Three traps hit while writing red-then-green bats tests for `remote-job.sh` (Refs #60, `dank/command-center` PR #61). Each one cost a detour because it makes a test look like a bug report when it is an assertion bug.
+
+## 1. In `[[ $s == pat ]]` a quoted `*` is LITERAL — and it eats the wildcard beside it
+
+```bash
+s='  x*                   DONE   rc=0  1 lines'
+[[ "$s" == *"x*"DONE*"rc=0"* ]]   # NOMATCH — and it looks like the tool under test broke
+[[ "$s" == "  x*"*"DONE   rc=0"* ]]   # MATCH — quoted literals, UNQUOTED separators
+```
+
+`*"x*"DONE*` means: anything, then the literal substring `x*DONE`, then anything. Quoting only makes the `*` inside the quotes literal; it does **not** keep the next unquoted token from butting up against it. When the subject has whitespace between the two facts, the pattern must carry an **unquoted** `*` between the quoted literals:
+
+```
+"literal-a"*"literal-b"      # a, then anything, then b
+```
+
+Existing suites in the repo write `*"a"*DONE*rc=0*` — unquoted separators throughout — precisely for this reason. Copy that shape; do not quote for "clarity".
+
+Discriminate before believing the test: run the pattern against BOTH the expected line and the line the buggy code produced (`correct-red` / `NOMATCH` on the second is the pass condition). A pattern that matches the old output was never a regression test.
+
+## 2. A bats failure dump prints the TEST's stdout, not `$output`
+
+```
+not ok 1 status treats a job name as a name, not a pattern
+#   `[[ "$output" == *"x*"DONE* ]]` failed
+# started x*
+```
+
+`started x*` is the stdout the test body itself printed (from a `start` call several lines earlier), **not** what `run` captured. Reading it as the captured value sends you to debug the tool. To see the real capture, echo it:
+
+```bash
+run some-command
+echo "CAP:[${output}]"
+```
+
+in a scratch copy of the test (`/tmp/dbg.bats`, same `setup`/harness) rather than adding diagnostics to the committed test.
+
+## 3. Reproduce outside bats when green refuses to arrive
+
+When a test fails but the same command works by hand, replicate the *exact* bats call shape in `/tmp` with the same env exports (`REMOTE_JOBS_DIR` etc.) and the same `run bash -c '…' _ "$A" "$B" "$C"` argument mapping. If the scratch copy passes and the committed one fails, the difference is the assertion, not the system — go back to trap 1.
+
+## Red-proof rule
+
+Run the new test against the pre-fix code and read *why* it failed. Both traps above produced a failure that looked meaningful while proving nothing (one matched the buggy output; one printed the wrong stream). Keep the test only when the failure reason is the defect you set out to pin.
+
+Related: `bats-assertion-trust` (vacuous assertions), `red-verify-without-stash` (proving red in a shared worktree).