fix(explorer): encode RFC 3986 reserved chars in query parameter values

Replaces the manual space-only encoding with encodeURIComponent for query
parameters, so reserved characters like ':' are correctly percent-encoded
(e.g. ':' → '%3A') when building request URLs.

Path parameters retain the existing whitespace-only encoding since they
are handled separately downstream in setPathParams.

Closes #1312

Author: sserrata

packages/docusaurus-theme-openapi-docs/src/theme/ApiExplorer/ParamOptions/ParamFormItems/ParamTextFormItem.tsx

@@ -38,9 +38,11 @@ export default function ParamTextFormItem({
           setParam({
             ...param,
             value:
-              param.in === "path" || param.in === "query"
+              param.in === "path"
                 ? e.target.value.replace(/\s/g, "%20")
-                : e.target.value,
+                : param.in === "query"
+                  ? encodeURIComponent(e.target.value)
+                  : e.target.value,
           })
         )
       }