Add terraform state registry (#36710)

Adds terraform/opentofu state registry with locking. Implements: https://github.com/go-gitea/gitea/issues/33644. I also checked [encrypted state](https://opentofu.org/docs/language/state/encryption), it works out of the box.

Docs PR: https://gitea.com/gitea/docs/pulls/357

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Co-authored-by: Andras Elso <elso.andras@gmail.com>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

templates/swagger/v1_json.tmpl

@@ -3835,6 +3835,7 @@
               "rpm",
               "rubygems",
               "swift",
+              "terraform",
               "vagrant"
             ],
             "type": "string",