fix(oxfmt): format HTML in a <script> body as an embedded part (#28379)

```html
<script type="text/html">
  <div style="color:red;background:blue" onclick="foo( 1 )" class="  a   b  ">x</div>
</script>
```

will be formatted:

```html
<script type="text/html">
  <div style="color:red;background:blue" onclick="foo( 1 )" class="  a   b  ">
    x
  </div>
</script>
```

Note attributes are NOT.

apps/oxfmt/conformance/fixtures/edge-cases/html/nested-html-in-script.html

@@ -0,0 +1,3 @@
+<script type="text/html">
+  <div style="color:red;background:blue" onclick="foo( 1 )" class="  a   b  ">x</div>
+</script>

apps/oxfmt/conformance/snapshots/conformance.snap.md

@@ -370,7 +370,7 @@
 
 ## html
 
-### Option 1: 617/623 (99.04%)
+### Option 1: 618/624 (99.04%)
 
 ```json
 {"printWidth":80}
@@ -389,7 +389,7 @@
 - [externals/vite/html/valid.html](diffs/html/externals__vite__html__valid.html.md)
   - crates/oxc_formatter_htmlish/DIVERGENCES.md#unquoted-value-with-slash
 
-### Option 2: 618/623 (99.20%)
+### Option 2: 619/624 (99.20%)
 
 ```json
 {"printWidth":100,"htmlWhitespaceSensitivity":"ignore","singleAttributePerLine":true}
@@ -406,7 +406,7 @@
 - [externals/vite/html/valid.html](diffs/html/externals__vite__html__valid.html.md)
   - crates/oxc_formatter_htmlish/DIVERGENCES.md#unquoted-value-with-slash
 
-### Option 3: 617/623 (99.04%)
+### Option 3: 618/624 (99.04%)
 
 ```json
 {"printWidth":120,"htmlWhitespaceSensitivity":"strict","bracketSameLine":true}

apps/oxfmt/src/core/embed/dispatcher.rs

@@ -26,6 +26,7 @@ use oxc_formatter_markdown::{MarkdownFormatOptions, XxxInMarkdownCodeBlock};
 use oxc_formatter_toml::TomlFormatOptions;
 use oxc_formatter_yaml::YamlFormatOptions;
 
+use super::jsdoc_fence::XxxInJsdocFence;
 use crate::core::{
     language::{Route, route_embedded},
     options::{
@@ -341,20 +342,19 @@ pub fn build_dispatcher(
                         dispatch_config.toml_options(),
                     ),
                     NativeLanguage::Html(variant) => {
-                        // Embedded in a JS template literal or a Markdown code block;
-                        // `None` is a part formatted on its own (a JSDoc code block).
-                        // An HTML parent added later needs its marker here, or reads as standalone.
-                        let embedded_in = request
-                            .parent_context_as::<HtmlInJsTemplate>()
-                            .map(|c| HtmlishEmbeddedIn {
-                                indent_multiple_roots: c.indent_multiple_roots,
-                                placeholder: Some(c.placeholder),
-                            })
-                            .or_else(|| {
-                                request
-                                    .parent_context_as::<XxxInMarkdownCodeBlock>()
-                                    .map(|_| HtmlishEmbeddedIn::default())
-                            });
+                        // Every part is embedded in its parent (Prettier's `parentParser`),
+                        // but a JSDoc code block, formatted on its own
+                        let embedded_in =
+                            if let Some(c) = request.parent_context_as::<HtmlInJsTemplate>() {
+                                Some(HtmlishEmbeddedIn {
+                                    indent_multiple_roots: c.indent_multiple_roots,
+                                    placeholder: Some(c.placeholder),
+                                })
+                            } else if request.parent_context_as::<XxxInJsdocFence>().is_some() {
+                                None
+                            } else {
+                                Some(HtmlishEmbeddedIn::default())
+                            };
                         oxc_formatter_htmlish::format_to_ir(
                             session,
                             text,

apps/oxfmt/src/core/embed/jsdoc_fence.rs

@@ -16,6 +16,11 @@ use oxc_formatter_core::{
 
 use super::dispatcher::ResolvedDispatchConfig;
 
+/// Parent→child context for a JSDoc fenced code block:
+/// a part formatted on its own, as Prettier formats it (`prettier.format`, no `parentParser`),
+/// where every other dispatched part is embedded in its parent.
+pub struct XxxInJsdocFence;
+
 /// The session's string embedder: [`format_native_fence`] over `fence_dispatcher`,
 /// a fallback-less registry (a native fence never falls back to Prettier).
 /// `sort_tailwind` is the root's pre-bound sorter, for the `@apply` classes a CSS fence collects.
@@ -76,7 +81,7 @@ fn format_native_fence(
                     language,
                     text: code,
                     input_kind: InputKind::Fragment,
-                    parent_context: None,
+                    parent_context: Some(&XxxInJsdocFence),
                 },
                 printer_options,
             )?