Remove htmx (#37224)

Close #35059

Slightly improved the "fetch action" framework and started adding tests for it.

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Signed-off-by: silverwind <me@silverwind.io>
Co-authored-by: silverwind <me@silverwind.io>

package.json

@@ -49,7 +49,6 @@
     "dropzone": "6.0.0-beta.2",
     "easymde": "2.20.0",
     "esbuild": "0.28.0",
-    "htmx.org": "2.0.8",
     "idiomorph": "0.7.4",
     "jquery": "4.0.0",
     "js-yaml": "4.1.1",