Ship herdr alongside tmux (#6406)

* Ship herdr with a config that mirrors our tmux setup

Installs herdr through the mise shim, ships the matching config as an
Omarchy default, and adds the usual refresh/restart pair. The keybindings
map tmux sessions to workspaces, windows to tabs, and keep both the prefix
and direct bindings from config/tmux/tmux.conf.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

* Add herdr versions of the tmux dev layout functions

hdl, hds, hdlm, and hsl drive herdr through its socket API instead of
tmux. hsl tiles into a real grid since herdr has no select-layout tiled.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

* Namespace the herdr layout helpers so they stay out of the shell

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

* Create hdlm's tabs in its own workspace instead of the focused one

herdr tab create follows the focused workspace without --workspace, so
switching workspaces while hdlm loops scatters the new tabs.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

* Lay hsl's grid out in visual order

Splitting the first column repeatedly inserted each new column between it
and the previous one, so uneven counts put the spare row in a middle
column instead of the last.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

* Report herdr config reload failures instead of swallowing them

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

* Hide herdr's pane scrollbars to match tmux

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

* Escape queued herdr layout commands

* Install herdr from the omarchy-herdr package instead of mise

* Use native herdr resize keybindings for tmux-style pane resizing

* Rename the omarchy-herdr package to herdr

---------

Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>

migrations/1786273938.sh

@@ -0,0 +1,19 @@
+echo "Install herdr from the Omarchy package repo and seed its config"
+
+# The package was briefly published as omarchy-herdr; herdr replaces it
+omarchy-pkg-drop omarchy-herdr
+omarchy-pkg-add herdr
+
+# An earlier revision of this migration installed herdr through mise. Drop that
+# install so a stale client can't shadow the packaged /usr/bin/herdr with an
+# older wire protocol.
+rm -f "$HOME/.local/bin/herdr"
+if mise ls herdr 2>/dev/null | grep -q herdr; then
+  mise unuse -g herdr &>/dev/null || true
+  mise uninstall -a herdr &>/dev/null || true
+fi
+rm -rf "$HOME/.local/share/mise/installs/herdr" "$HOME/.local/share/mise/shims/herdr"
+
+# Only seed. A user who already has a herdr config keeps it; omarchy-refresh-herdr
+# is the explicit way to take the shipped defaults.
+[[ -f "$HOME/.config/herdr/config.toml" ]] || omarchy-refresh-config herdr/config.toml