[Improvement] herdr one-shot layout helpers (agent workdesks)

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Quattro feature

Omarchy 4 ships one-shot multiplexer layout functions and mirrored them onto herdr when it adopted it: hdl <agent> (editor left, agent right, terminal bottom), hds (four-way: editor, live diff watcher, terminal, agent), hdlm (one layout per subdirectory), hsl <count> <cmd> (tiled grid).

Omacase fit

Omacase just dropped tmux (herdr + Ghostty cover multiplexing), which removed the traditional way power users assembled work layouts. herdr-native layout aliases restore that at a higher level — and Omacase already integrates herdr deeply (state hooks; herdr self-installs its skill). This deepens the differentiating herdr story rather than adding surface.

Proposed shape

• Shell functions in the managed dot_zshrc (or a lib/wm.sh-backed omacase desk <layout> [agent]), driving herdr's pane/tab API: hdl editor+agent+terminal, hds adds a live diff watcher pane, hdlm per-subdirectory workspaces
• Default agent (issue [Improvement] Default-agent abstraction: omacase agent + launch keybind + shell alias #22) supplies the agent when none is named
• Which herdr commands to drive: consult the herdr skill file (herdr --skill) — it documents pane/tab/workspace control; keep Omacase to thin composition, upstream anything missing to herdr itself

Scope

Future release. Depends on #22 for defaults; coordinate with herdr upstream before building (some layouts may belong there).

🤖 Generated with Claude Code

[splaice]

Implementation plan

Self-contained; needs only this comment and the repo. Depends on #22 (supplies the default agent name). First step is reconnaissance, not code.

Background

Omacase dropped tmux (herdr + Ghostty cover multiplexing); Quattro ships one-shot layout functions and mirrored them for herdr (hdl editor|agent, hds four-way with live diff watcher, hdlm per-subdirectory, hsl tiled grid). Omacase already integrates herdr (state hooks via _herdr_integrations in lib/install.sh; herdr self-installs its own skill). The layout helpers are thin composition over herdr's pane/tab/workspace API.

Step 0 — pin the herdr API (do this before writing anything)

herdr --skill prints the agent-facing control documentation; herdr --help the CLI. From those, pin the exact verbs for: create workspace/tab, split pane horizontal/vertical with a command, focus pane, list subdirectories→workspace mapping. Record the pinned invocations + herdr version at the top of the new lib file. If a needed verb is missing, stop and file the gap upstream (herdr is maintainer-owned) rather than shimming around it — note which layouts are blocked and ship the subset.

Change 1 — lib/desk.sh (new): omacase desk <layout> [agent]

• omacase desk dl [agent] — editor ($EDITOR, default nvim) left, agent right, terminal bottom-right; agent defaults to omacase agent default ([Improvement] Default-agent abstraction: omacase agent + launch keybind + shell alias #22), overridable by arg.
• omacase desk ds [agent] — four-way: editor, live diff (git diff --watch isn't a thing — use viddy git diff if viddy present else a while :; do clear; git diff --stat; sleep 2; done fallback; note Quattro uses hunk diff --watch, not in our stack), terminal, agent.
• omacase desk dlm [agent] — one herdr workspace per first-level subdirectory of $PWD (bounded: warn and take the first 9), each running the agent in that subdir.
• omacase desk sl <count> <cmd…> — tiled grid of N panes running cmd.
• All: require have herdr (abort with hint), require a herdr session/server per the pinned API (start one if the API supports it headlessly).

Change 2 — shell ergonomics + wiring

• home/dot_zshrc: hdl() { omacase desk dl "$@"; } hds() … hdlm() … hsl() … — thin, so the logic stays testable in lib/.
• bin/omacase usage + dispatch; completion (desk layouts + agent names from [Improvement] Default-agent abstraction: omacase agent + launch keybind + shell alias #22's _AGENTS table); menu entry optional — these are terminal-context commands, skip the menu.
• KEYBINDS.md: mention the four functions in the terminal section.

Change 3 — tests

herdr may be absent/headless in CI (macOS runner: brew-installed? it IS in the Brewfile, but a server may not start in CI):

1. Shim-based: PATH-shim herdr recording argv; omacase desk dl claude → recorded invocations match the pinned API sequence exactly (this is the real test — layout = command sequence).
2. dlm bounding: temp dir with 12 subdirs → exactly 9 workspace creations + a warn.
3. sl arg validation; missing herdr → abort message.
4. zshrc functions exist (grep).

Verification / done criteria

Suite green; shellcheck clean. Live on the dev machine: each of the four layouts assembles correctly in a real herdr session with the default agent; hdl from a repo gives editor+agent+terminal.

Branch + PR; body says Closes #25. If Step 0 finds upstream gaps, the PR ships the working subset and links the herdr issues filed.