Merge some standalone Vite entries into index.js (#37085)

Keep `swagger` and `external-render-helper` as a standalone entries for
external render.

- Move `devtest.ts` to `modules/` as init functions
- Make external renders correctly load its helper JS and Gitea's current theme
- Make external render iframe inherit Gitea's iframe's background color to avoid flicker
- Add e2e tests for external render and OpenAPI iframe

---------

Co-authored-by: Claude (Opus 4.6) <noreply@anthropic.com>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

routers/web/misc/swagger.go

@@ -6,15 +6,9 @@ package misc
 import (
 	"net/http"
 
-	"code.gitea.io/gitea/modules/templates"
 	"code.gitea.io/gitea/services/context"
 )
 
-// tplSwagger swagger page template
-const tplSwagger templates.TplName = "swagger/ui"
-
-// Swagger render swagger-ui page with v1 json
 func Swagger(ctx *context.Context) {
-	ctx.Data["APIJSONVersion"] = "v1"
-	ctx.HTML(http.StatusOK, tplSwagger)
+	ctx.HTML(http.StatusOK, "swagger/openapi-viewer")
 }

routers/web/repo/render.go

@@ -42,7 +42,9 @@ func RenderFile(ctx *context.Context) {
 	rctx := renderhelper.NewRenderContextRepoFile(ctx, ctx.Repo.Repository, renderhelper.RepoFileOptions{
 		CurrentRefPath:  ctx.Repo.RefTypeNameSubURL(),
 		CurrentTreePath: path.Dir(ctx.Repo.TreePath),
-	}).WithRelativePath(ctx.Repo.TreePath).WithInStandalonePage(true)
+	}).WithRelativePath(ctx.Repo.TreePath).WithStandalonePage(markup.StandalonePageOptions{
+		CurrentWebTheme: ctx.TemplateContext.CurrentWebTheme(),
+	})
 	renderer, rendererInput, err := rctx.DetectMarkupRendererByReader(blobReader)
 	if err != nil {
 		http.Error(ctx.Resp, "Unable to find renderer", http.StatusBadRequest)

routers/web/web.go

@@ -260,7 +260,7 @@ func Routes() *web.Router {
 	routes.BeforeRouting(chi_middleware.GetHead)
 
 	routes.Head("/", misc.DummyOK) // for health check - doesn't need to be passed through gzip handler
-	routes.Methods("GET, HEAD, OPTIONS", "/assets/*", routing.MarkLogLevelTrace, optionsCorsHandler(), public.FileHandlerFunc())
+	routes.Methods("GET, HEAD, OPTIONS", "/assets/*", routing.MarkLogLevelTrace, public.AssetsCors(), public.FileHandlerFunc())
 	routes.Methods("GET, HEAD", "/avatars/*", avatarStorageHandler(setting.Avatar.Storage, "avatars", storage.Avatars))
 	routes.Methods("GET, HEAD", "/repo-avatars/*", avatarStorageHandler(setting.RepoAvatar.Storage, "repo-avatars", storage.RepoAvatars))
 	routes.Methods("GET, HEAD", "/apple-touch-icon.png", misc.StaticRedirect("/assets/img/apple-touch-icon.png"))