Add syntax highlighting for all httpsnippet languages

Added 15 new EditorLanguage variants: c, clojure, csharp, go, java,
kotlin, objective_c, ocaml, php, powershell, python, r, ruby, shell,
swift.

Uses first-class CodeMirror packages for go, java, php, python and
@codemirror/legacy-modes for the rest. Also sorts preferred clients
(fetch) to the top for JavaScript/Node targets.

package.json

@@ -105,5 +105,12 @@
     "npm-run-all": "^4.1.5",
     "typescript": "^5.8.3",
     "vitest": "^3.2.4"
+  },
+  "dependencies": {
+    "@codemirror/lang-go": "^6.0.1",
+    "@codemirror/lang-java": "^6.0.2",
+    "@codemirror/lang-php": "^6.0.2",
+    "@codemirror/lang-python": "^6.2.1",
+    "@codemirror/legacy-modes": "^6.5.2"
   }
 }