feat(core): Add PKCE for OAuth2 (#6324)

* Remove authorization header when empty

* Import pkce

* Add OAuth2 with new grant type to Twitter

* Add pkce logic auto assign authorization code if pkce not defined

* Add pkce to ui and interfaces

* Fix scopes for Oauth2 twitter

* Deubg + pass it through header

* Add debug console, add airtable cred

* Remove all console.logs, make PKCE in th body only when it exists

* Remove invalid character ~

* Remove more console.logs

* remove body inside query

* Remove useless grantype check

* Hide oauth2 twitter waiting for overhaul

* Remove redundant header removal

* Remove more console.logs

* Add comment for code verifier

* Remove uneeded scopes

* Restore client id in callback

* Revert "Add OAuth2 with new grant type to Twitter"

This reverts commit 1c3b331aa1974159d1ffe1a4fbf2050722f0f24c.

* Remove oauth2 from twitter

* Remove properties linked to oauth2

* Fix lodash imports

* remove redundant check

* remove redundant codeVerifier

* patch pkce-challenge to avoid generating `code_verifier` with `~`

* store `codeVerifier` on the DB like `csrfSecret`

* remove unrelated changes

---------

Co-authored-by: Marcus <marcus@n8n.io>
Co-authored-by: कारतोफ्फेलस्क्रिप्ट™ <aditya@netroy.in>

package.json

@@ -94,7 +94,8 @@
     "patchedDependencies": {
       "element-ui@2.15.12": "patches/element-ui@2.15.12.patch",
       "typedi@0.10.0": "patches/typedi@0.10.0.patch",
-      "@sentry/cli@2.17.0": "patches/@sentry__cli@2.17.0.patch"
+      "@sentry/cli@2.17.0": "patches/@sentry__cli@2.17.0.patch",
+      "pkce-challenge@3.0.0": "patches/pkce-challenge@3.0.0.patch"
     }
   }
 }