fix(ui): loud clipboard denial, mid-width kill verb, phone legibility (dogfood 2026-08-24)

[minglong51]

What

Frontend fixes from the 2026-08-24 dogfood walk of the live fleet dashboard (founder-agent-os/prototypes/dogfood-reports-2026-08-24/agent-usage-manager.md). All changes are in agent_usage_manager/static/index.html (+ regression test + LLD §6 line-cite refresh per the design-doc contract).

Bug #1 — click-to-copy failed silently when the clipboard write was denied

copyHint was navigator.clipboard?.writeText(...).then(...) with no .catch. A denied write (permission, unfocused document — reproduced live in the walk) produced no "copied ✓", no error, nothing on the clipboard: the operator walks away believing they hold a bootout command they don't have.

Now a rejection (or missing clipboard API) flashes "copy failed — press ⌘C" on the chip, then restores the command and selects it so a manual copy is one keystroke away (an active selection also pauses auto-refresh via the existing refresh() guard, so the re-render can't yank it). An el.isConnected guard covers the race where a poll re-renders the row mid-flash, keeping the console clean.

Bug #2 — 701px–~1494px dead zone hid the only kill verb

The all-nowrap table measures ~1.5kpx; .wrap scrolls horizontally and the actions column — the last one — sat off-screen until scrolled to, while the stacked phone layout only engages ≤700px. A half-screen desk window landed in a dead zone: full chrome, no reachable verb.

The actions column (.c-act) is now position: sticky; right: 0 above the phone breakpoint, with text-align: right so the verbs hug the pinned edge (the nowrap launchctl hint chips inflate the column to ~454px). Phone rows are stacked blocks with no horizontal overflow, so the rule is scoped min-width: 701px.

F1/F2/F3 — phone legibility

• F1: stacked rows rendered 1.0 155 with no units (headers hidden, title tooltips unreachable on touch). .unit spans — hidden on desk where the headers carry the units, shown in the phone stack → 1.0% 155 MB (main + child rows).
• F2: child rows lost .c-cmd at ≤700px — their only identity ("↳ 2.1.241 0.0 34"). Child cmdline now stays in the phone layout, wrapped (overflow-wrap: anywhere).
• F3: the 110px end-ellipsis clamp rendered every supervised row's chip as the identical "launchctl boot…", ellipsing the job label — the one part that differs. Now truncates from the left (direction: rtl, 240px) → "…501/ai.hermes.gateway-frontdoor". Click-to-copy still copies the full text.

Validation

• Tests: pytest tests/ — 75 passed (includes new test_index_frontend_regressions pinning the served page's behavior-bearing markup; no JS runner in this repo).
• Behavioral (gstack browse harness against an isolated instance on :8766 with an alerts-stripped config; the live :8765 service was never restarted and no kill verb was clicked):
  • Bug docs: design-doc upkeep contract + drift checker #2: at 800px unscrolled — 0/40 kill buttons visible before, 40/40 after + 5/5 launchctl chips; at 1440px 40/40 + 5/5 (table is 1496px wide, so even "full" desk width overflowed by 56px before). Before/after screenshots: /tmp/aum-before-midwidth-800.png / /tmp/aum-fix-midwidth-800.png; desk: /tmp/aum-fix-desk-1440.png.
  • Bug Match GUI + launchd-supervised agents on macOS, hardened from triad review #1: denial simulated by overriding writeText to reject with NotAllowedError — MutationObserver recorded "copy failed — press ⌘C" at t=1ms, command restored + fully selected at t=1503ms; success path still flashes "copied ✓" (stubbed resolve). Screenshot: /tmp/aum-fix-copy-failed.png. Console clean.
  • Phone (390×760): rows render 4.8% 259 MB; expanded children show full wrapped cmdlines; supervised chips read "…/ai.hermes.gateway-engineer_5" etc. — each distinguishable. Screenshots: /tmp/aum-fix-phone-tree.png, /tmp/aum-fix-phone-hint.png.

Deferred (follow-up PR, per assignment scope)

• F4: the chronic idle 10m+ daemon row pinned top forever — idle_ok: matches on row label (app.py:1201-1209) and the daemon shares claude-code with every interactive session; needs cmdline-granular suppression (e.g. idle_ok_match:). A config-semantics change, deliberately not in this frontend PR.
• Pre-existing doc drift (unrelated): test_design_docs.py flags agents.default.yaml as added-but-unnamed in the LLD.

F5 (native confirm/prompt chrome) and F6 (keyboard a11y on the +N/hint spans) also remain open from the report.