A test pins keeping a thought: signed out is refused, a body that is not text is refused, and nothing is stored #7115

keepThought in src/actions/thought.ts refuses unauthorized and not_text, and no test names not_text.

Done:

• [ ] A new test keeps a text thought, and it is answered with an id and receivedAt.
• [ ] A number, an object and null are each not_text. Signed out is unauthorized.
• [ ] After each refusal, no thought row exists.

Files: test/thought-refusals.test.ts

If the test finds the behaviour wrong, fix the action in the same pull and say so.

If the check fails in a test this pull does not touch, name it in the pull rather than widening the change.

Before pushing: bun x tsc --noEmit and the tests this names.