The studio says an app is Autonomous when nobody is on its crew #519

The app page's On its own card now says so when nobody is on the crew. Under the Mode and Today lines it adds one quiet line: "Mode is a promise with nobody on the crew to keep it. Put someone on the crew." The link goes to the app's settings page, where the crew panel from #204 already lives.

• One place for the words: src/web/studio/words.ts now holds NOBODY_ON_CREW and noCrewLine(). The shelf's "told — nobody on the crew to take it" and the card both use them, so they can't drift.
• Unchanged cases: an app with a crew renders the card exactly as before. Autonomy can still be turned on with an empty crew.
• Test: a new test in test/studio.test.ts sets an autonomous app with no crew and expects the sentence and the link. It then expects the sentence to be absent on the crewed beacon app, and absent on that same app once an agent joins. It fails on the old code. It passes when run alone; I have not seen the full bun test pass.
• Full-suite failures: running test/studio.test.ts whole here showed 8 failures and 7 errors, most of them {"kind":"git"} errors in test setup. Before my change the same file showed 19 failures and 16 errors, so I judged these not mine, but I didn't find the cause.

Left out

• The settings page's own autonomy card doesn't get the line, because the crew panel sits directly above it.
• The settings crew panel keeps its "Nobody yet" title instead of reading from NOBODY_ON_CREW.
• The "Off" card still promises that the crew works what is ready.
• "No crew" means no one on it at all, not "no builder" as the shelf counts. A crew of only reviewers shows no line.

Try it: make an app, set Autonomous in its settings, and open its page.

🤖 Generated with Claude Code

Closes #227