Ctrl+hjkl navigation broken on herdr 0.7.0 (pane-id format + focus API changes)

[ctbaum]

Summary

herdr-navigator no longer navigates between panes on herdr 0.7.0 — every focus/dispatch exits non-zero and focus never moves. herdr.nvim is at current main (deed849). herdr's own herdr pane neighbor / herdr pane focus CLI work fine, so the live layout/state is healthy — it's the helper's assumptions about 0.7.0 that broke. There are two independent incompatibilities.

1. Pane-id format — pane_public_mapping

It builds public ids as "{workspace_id}-{index+1}" (e.g. w3-1):

.map(|(index, internal_id)| (internal_id, format!("{workspace_id}-{}", index + 1)))

But herdr 0.7.0's public pane ids are "{workspace}:p{number}" (e.g. w3:p3) — the form used by pane.list, pane.current, HERDR_ACTIVE_PANE_ID, etc. So internal_id_from_pane_id("w3:p3", …) never matches the generated w3-1/w3-2/…, then falls through to "w3:p3".parse::<i64>() (fails) → None → focus_adjacent returns Ok(1). Every pane lookup fails, so all navigation is dead.

The correct internal→public mapping is already in session.json on the workspace as public_pane_numbers, e.g.:

"public_pane_numbers": { "10": 3, "9": 2, "14": 6, "8": 1 }

i.e. for each internal id, build format!("{workspace_id}:p{public_number}") using public_pane_numbers[internal].

2. Focus API — focus_pane / focus_adjacent

The agent.focus shim (report_agent → agent.focus → release_agent) no longer moves focus on 0.7.0 — the RPCs succeed but server focus doesn't change. AGENTS.md notes the shim exists "since Herdr has no direct pane.focus API", but 0.7.0 added one: pane.focus_direction, with params { "pane_id": "<id>", "direction": "left|right|up|down" }. It computes the neighbor and focuses it server-side in a single call (it's what herdr pane focus --direction uses), which also makes the session.json layout math unnecessary for focusing.

Environment

• herdr 0.7.0 (Homebrew, macOS / Apple Silicon)
• herdr.nvim main @ deed849

Repro

With ≥2 panes in a tab, Ctrl+h/j/k/l doesn't move between panes. From a shell:

HERDR_ACTIVE_PANE_ID=<a-pane-id> HERDR_ACTIVE_TAB_ID=<its-tab-id> herdr-navigator focus left; echo $?
# -> exits 1, no focus change

(herdr pane neighbor --direction left --pane <a-pane-id> returns the correct neighbor, confirming the live layout is fine.)

Proposed fix

Both are small: derive ids from public_pane_numbers ({ws}:p{n}), and have focus_adjacent call pane.focus_direction (falling back to the existing computed path if the RPC is unavailable, for older herdr). I've applied exactly this locally and navigation is fully restored.

Happy to open a PR if that's welcome — just let me know your preference and I'll run it through the repo's cargo fmt / clippy / pre-commit checks first. Thanks for the plugin!