Fixed: builds that died quietly, sites that wouldn't delete

The unglamorous half of the week. All of these were things that went wrong quietly, which is the worst way for something to go wrong.

What's fixed

• A slow build reports instead of vanishing. Generation now runs against a wall-clock budget and tells you where it got to, rather than being cut off mid-sentence and leaving you looking at a spinner that never resolves.
• One unescaped apostrophe can't take a site down anymore. A file that didn't parse used to get sent back to the AI for a 40-second retry that often returned the identical file — one build spent four attempts and most of its time on a single quote and shipped nothing. That specific break is now repaired directly, and only accepted when the file provably parses better than before.
• The first questions no longer stop at 60 seconds. The intake step could hit a hard ceiling and die without a word; it now finishes or tells you.
• Deleting a website works, every time. A site that had ever received a contact-form message couldn't be deleted at all — the delete failed on a leftover reference. Every delete path now clears the same complete list of records, and hosting, files and repository are torn down with it.
• Deleting an account leaves nothing dangling. No more admin notifications linking to a user who no longer exists, and no more half-finished builds left stuck as "generating" with no owner.

Fairer credits

Credits for an AI change now follow what the change actually cost to run, instead of a flat count per page. Long, output-heavy work costs a little more than it used to; short input-heavy edits cost less. Overall billing landed within a fraction of a percent of where it was — the difference is that individual charges now match the work. There's still a 10-credit minimum on any change, and a change that fails is refunded.