Row action linking to update SQL

[simonw]

Refs:

• 10

Still needed:

• [x] Automated tests
• [x] Manually test that the null handling works and makes sense
• [x] Sign the redirect_to argument to prevent abuse
• [x] Solution for if there are columns called sql or database or redirect_to - avoid clashes in query string parameters
• ~Smarter detection of fields that should be textareas, see comment https://github.com/simonw/datasette-write/issues/10#issuecomment-2004431721~ skipped for scope creep

[simonw]

Demo so far:

[simonw]

I decided to pass ?_title=... as a signed parameter too - if that's present it shows that title and hides the SQL behind a <details> thing like this:

Additionally, the primary key columns used to look up the value to edit are now sent as ?id_hidden=... and are hidden on that page.