docs: Herdr boot persistence applied and verified

/boot/config/go now restores /root/.local/bin/herdr-core from
/boot/config/herdr/herdr-core at boot, with install -m 755 since /boot is
FAT32 and carries no execute bit.

Verified without rebooting: deleted the binary, ran the go line by hand, got
it back executable and reporting hc 0.1.17, with Herdr still connected.
sh -n /boot/config/go parses cleanly. The go script was backed up to
go.bak-20261103-203916 before editing.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

docs/14-HERDR-REMOTE-MACHINES.md

@@ -96,4 +96,14 @@ install -m 755 /boot/config/herdr/herdr-core /root/.local/bin/herdr-core 2>/dev/
 
 `install -m 755` matters: `/boot` is FAT32 and does not carry the execute bit.
 
-**Status: not applied.** Pending.
+**Status: applied 2026-11-03.** The `go` script was backed up to
+`/boot/config/go.bak-20261103-203916` first.
+
+Verified without rebooting, by deleting `/root/.local/bin/herdr-core` and running
+the `go` line by hand: the binary came back `-rwxr-xr-x` and reported `hc 0.1.17`.
+Herdr stayed `connected` throughout.
+
+One note if you ever call it over a bare SSH command: `~/.local/bin` is not on
+`PATH` in a non-interactive shell on Unraid, so `herdr-core` resolves only by
+absolute path. Herdr itself always uses the absolute path, so this does not
+affect normal use.