Throw `GitHubProjectInvalidValueError` error when text is too long for text field (1024+ bytes)

### Please avoid duplicates

- [x] I checked [all open bugs](https://github.com/gr2m/github-project/issues?q=is%3Aissue+is%3Aopen+label%3Abug) and none of them matched my problem.

### Reproducible test case

see test/recorded/api.items.add-draft-with-too-long-text/fixtures.json

### Please select the environment(s) that are relevant to your bug report

- [ ] Browsers
- [ ] Node
- [ ] Deno

### Versions

5.3.0, Node v18.18.0

### What happened?

follow up to https://github.com/gr2m/github-project/issues/142. We introduced a workaround via #143, but the problem can still occur.

### Would you be interested in contributing a fix?

- [ ] yes

Beginne mit test/recorded/api.items.add-draft-with-too-long-text/fixtures.json und überprüfe die in #143 eingeführte Umgehungslösung sowie den nachfolgenden Kontext in #142. Reproduziere den Textfall mit 1024+ Bytes und verifiziere, dass er GitHubProjectInvalidValueError auslöst, anstatt dass der API-Fehler nach außen dringt.

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