fix(skills): repair butler cron and doc drift (2026-07-22 audit)

[IceyLiu]

Summary

Daily drift audit (2026-07-22) found two breaking issues and two doc
problems in the butler's built-in skills. This PR fixes all four.
Changes are asset-only — no .rs changes — and ship to users via
include_dir! on the next binary build.

Fixes

B1 — aionui-config: cron jobs update schedule field type (BREAKING)

The update example used "schedule": "0 10 * * MON" (flat string). The
backend UpdateCronJobRequest.schedule is Option<CronScheduleDto>
(crates/aionui-api-types/src/cron.rs:203-204) — the same internally-tagged
object as create. A plain string fails to deserialize and the request
errors out. Fixed the example to { "kind": "cron", "expr": "0 10 * * MON" }
and added a note distinguishing the two cron families (cron jobs uses
tagged object; cron current uses flat string).

B2 — aionui-troubleshooting: cron field names/paths (BREAKING → misdiagnosis)

The skill told the reading agent to look at top-level last_status,
next_run_at, last_run_at etc. These don't exist there. All run-state
fields are nested under state in CronJobResponse
(crates/aionui-api-types/src/cron.rs:113-140), and the timestamp fields
carry _ms suffixes. The agent would silently find nothing and misreport
cron state. Corrected to state.last_status, state.last_error,
state.next_run_at_ms, state.last_run_at_ms, etc.
Also added a fallback hint for the cron.failing overview field being
empty (see backend bug report linked below).

D1 — aionui-config: default_mcp_ids → defaults.mcps

Prose at line 149 named default_mcp_ids as a settable field on assistant
update. No such field exists on UpdateAssistantRequest; MCP defaults are
set via defaults.mcps (assistant.rs:164). Without deny_unknown_fields,
the old name was silently ignored. Corrected the prose.

D2 — aionui-config: agents custom test → try-connect

The prose said "test a custom agent" but the actual subcommand is
try-connect (cmd_config.rs:800-808). Renamed and added a minimal
example.

How verified

Every fix was verified against file:line in the freshly-pulled main
(10cdd579) before editing:

• UpdateCronJobRequest: cron.rs:203-204
• CronJobStateDto nesting: cron.rs:113-140
• AssistantDefaultsRequest.mcps: assistant.rs:164
• try-connect dispatch: cmd_config.rs:800-808

Related

Backend bug (not in this PR): diagnose cron summary / overview read
last_status at the wrong depth (cmd_diagnose.rs:764, 783), so
cron.failing is always empty. A separate issue is filed for that .rs
fix.

Deploy path

Asset-only change. Ships via include_dir! in aionui-app when the
binary is rebuilt. No migration, no schema change.