refactor(skills): consolidate managed skill library 94 -> 25

The managed-skill library was regenerated: 94 narrow per-incident skills
replaced by 25 broader ones (radiance-*, llamacpp-*, homepage-*, fleet/
endpoint ops). Git renders this as mass delete + mass add because whole
directories changed name; old content stays in history at 12c5e88.

Surface check: the 25 on disk are exactly the skills the harness advertises
this session.

agent/managed-skills/detached-fleet-job-launch/SKILL.md

@@ -0,0 +1,46 @@
+---
+name: detached-fleet-job-launch
+description: Launch a long-running remote job on Dank fleet hosts so it survives ssh/logind teardown
+---
+
+# Detached long-running jobs on Dank fleet hosts
+
+## Law
+`ssh host 'setsid nohup CMD & '` is NOT detached. systemd-logind deactivates
+`session-N.scope` when the ssh command returns and SIGKILLs the whole cgroup:
+no journal entry, no OOM trace, python block-buffers stdout so the log stays
+0 bytes. setsid/nohup do not escape the cgroup.
+
+## Canonical launch
+```
+ssh host 'export XDG_RUNTIME_DIR=/run/user/$(id -u); \
+  systemd-run --user --collect --unit=NAME \
+    -p SendSIGKILL=no \
+    -p StandardOutput=append:/home/dank/logs/NAME.log \
+    -p StandardError=append:/home/dank/logs/NAME.log \
+    sh -c "CMD -u; echo \$? > /home/dank/logs/NAME.rc"'
+```
+- transient user unit = outside every session scope; survives ssh teardown
+  (requires `Linger=yes`, true for `dank` on both hosts)
+- `echo $? > …rc` inside the unit = completion sentinel the unit itself writes
+- `-u` / unbuffered output so the log is live
+- verify launch in the same ssh call: `systemctl --user is-active NAME.service`
+
+## Watcher (one async job, never poll)
+```
+ssh host 'while [ ! -f /home/dank/logs/NAME.rc ]; do sleep 60; done; \
+  echo RC=$(cat /home/dank/logs/NAME.rc); tail -25 /home/dank/logs/NAME.log'
+```
+Run it async with timeout 0; the result is injected on completion.
+
+## Forensics when a detached job died
+1. `ps -p PID` — gone.
+2. Log 0 bytes → buffered stdout lost at SIGKILL.
+3. `journalctl --since … | grep -E "session-[0-9]+.*(Deactivated|Removed session)"` —
+   timestamps matching the death window confirm the scope kill (vs OOM, which
+   leaves kernel lines).
+
+## Notes
+- zsh remote shells: `echo ===X===` fails (`=cmd` expansion); quote sentinels.
+- The HF upload of 2026-10-08 (113.7 GiB, hf_xet) died this way ~2 min in;
+  relaunch as above succeeded.