fix: 3.11.1 — a skill-only install still has the CLI, and the advertised install is one skill

[devin-ai-integration]

Summary

I ran the one path that had never been tested — npx skills add suboss87/fdeops — and it succeeded, which is how both of these surfaced. It installs the method and nothing else, so the FDE ends up with a router that has no hands.

1. The router's CLI fallback didn't exist off Claude Code.

fde resume  →  node ~/.claude/fdeops/fde.js resume  →  (nothing)  →  "CLI missing → write files by hand"

~/.claude/fdeops/ only exists after npx fdeops has run the installer. On Cursor/Codex/anything skills-compatible, a skills add user hit the manual path on their first deterministic command — losing dating, the ship/eval gates and <private> redaction, i.e. the reasons the CLI exists. The fallback chain now ends at npx --yes fdeops <verb>, verified end-to-end on a clean HOME with nothing installed:

$ HOME=/tmp/npxpath/home npx --yes fdeops resume --init acme
TRIAGE  [green ]  phase:unset  updated:today  open risks:0
ENGAGEMENT: /tmp/npxpath/home/fde-engagements/acme/.fde

"CLI unavailable" is now defined as no Node or no network — not "not installed".

2. The advertised install shipped a contributor skill. skills add discovers .agents/skills/ too, so a field user also got testing-fieldbook (how to adversarially test this repo's own CLI):

$ npx skills add suboss87/fdeops
✓ fde (copied)                 → ./.agents/skills/fde
✓ testing-fieldbook (copied)   → ./.agents/skills/testing-fieldbook

That skill has to stay where it is (it is the agent-skills location), so the README now documents --skill fde and a gate fails the build on any npx skills add line in the README that doesn't pin it. A second gate asserts the SKILL.md npx fallback, so a future edit can't quietly re-strand skill-only users.

Docs + one router paragraph + two gates; no CLI behaviour change. npm run check green, 119/119.

Link to Devin session: https://app.devin.ai/sessions/f135381c4682413bae73dff38eb6d1a3
Open in Devin Desktop: https://app.devin.ai/desktop/session/f135381c4682413bae73dff38eb6d1a3?variant=devin
Requested by: @suboss87

[devin-ai-integration]

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