Backport #27267 by @silverwind
1. Dropzone attachment removal, pretty simple replacement
2. Image diff: The previous code fetched every image twice, once via
`img[src]` and once via `$.ajax`. Now it's only fetched once and a
second time only when necessary. The image diff code was partially
rewritten.
Co-authored-by: silverwind <me@silverwind.io>
WIP because:
- [x] Some calls set a `content-type` but send no body, can likely
remove the header
- [x] Need to check whether `charset=utf-8` has any significance on the
webauthn calls, I assume not as it is the default for json content.
- [x] Maybe `no-restricted-globals` is better for eslint, but will
require a lot of duplication in the yaml or moving eslint config to a
`.js` extension.
- [x] Maybe export `request` as `fetch`, shadowing the global.
1. Introduce lightweight `fetch` wrapper functions that automatically
sets csfr token, content-type and use it in `RepoActionView.vue`.
2. Fix a specific issue on `RepoActionView.vue` where a fetch network
error is shortly visible during page reload sometimes. It can be
reproduced by F5-in in quick succession on the actions view page and was
also producing a red error box on the page.
Once approved, we can replace all current `fetch` uses in UI with this
in another PR.
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Co-authored-by: Giteabot <teabot@gitea.io>
