Replace CSRF cookie with CrossOriginProtection (#36183)

Removes the CSRF cookie in favor of
[`CrossOriginProtection`](https://pkg.go.dev/net/http#CrossOriginProtection)
which relies purely on HTTP headers.

Fixes: https://github.com/go-gitea/gitea/issues/11188
Fixes: https://github.com/go-gitea/gitea/issues/30333
Helps: https://github.com/go-gitea/gitea/issues/35107

TODOs:

- [x] Fix tests
- [ ] Ideally add tests to validates the protection

---------

Signed-off-by: wxiaoguang <wxiaoguang@gmail.com>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

web_src/js/features/dropzone.ts

@@ -8,7 +8,7 @@ import {createElementFromHTML, createElementFromAttrs} from '../utils/dom.ts';
 import {isImageFile, isVideoFile} from '../utils.ts';
 import type {DropzoneFile, DropzoneOptions} from 'dropzone/index.js';
 
-const {csrfToken, i18n} = window.config;
+const {i18n} = window.config;
 
 type CustomDropzoneFile = DropzoneFile & {uuid: string};
 
@@ -73,7 +73,6 @@ export async function initDropzone(dropzoneEl: HTMLElement) {
   let fileUuidDict: FileUuidDict = {}; // to record: if a comment has been saved, then the uploaded files won't be deleted from server when clicking the Remove in the dropzone
   const opts: Record<string, any> = {
     url: dropzoneEl.getAttribute('data-upload-url'),
-    headers: {'X-Csrf-Token': csrfToken},
     acceptedFiles: ['*/*', ''].includes(dropzoneEl.getAttribute('data-accepts')!) ? null : dropzoneEl.getAttribute('data-accepts'),
     addRemoveLinks: true,
     dictDefaultMessage: dropzoneEl.getAttribute('data-default-message'),

web_src/js/features/pull-view-file.ts

@@ -28,7 +28,7 @@ export function initViewedCheckboxListenerFor() {
     // To prevent double addition of listeners
     form.setAttribute('data-has-viewed-checkbox-listener', String(true));
 
-    // The checkbox consists of a div containing the real checkbox with its label and the CSRF token,
+    // The checkbox consists of a div containing the real checkbox with its label,
     // hence the actual checkbox first has to be found
     const checkbox = form.querySelector<HTMLInputElement>('input[type=checkbox]')!;
     checkbox.addEventListener('input', function() {

web_src/js/features/repo-settings.ts

@@ -5,7 +5,7 @@ import {initRepoSettingsBranchesDrag} from './repo-settings-branches.ts';
 import {fomanticQuery} from '../modules/fomantic/base.ts';
 import {globMatch} from '../utils/glob.ts';
 
-const {appSubUrl, csrfToken} = window.config;
+const {appSubUrl} = window.config;
 
 function initRepoSettingsCollaboration() {
   // Change collaborator access mode
@@ -56,7 +56,6 @@ function initRepoSettingsSearchTeamBox() {
     rawResponse: true,
     apiSettings: {
       url: `${appSubUrl}/org/${searchTeamBox.getAttribute('data-org-name')}/teams/-/search?q={query}`,
-      headers: {'X-Csrf-Token': csrfToken},
       onResponse(response: any) {
         const items: Array<Record<string, any>> = [];
         for (const item of response.data) {