fix(linter): preserve source text for JS plugin ignore fixes

[NriotHrreion]

Closes #25278

Overview

This PR resolves an oxlint language server crash that could occur when requesting code actions for diagnostics reported by JS plugins, particularly when the diagnostic appears after the beginning of a file.

JS plugin diagnostics can now safely provide regular fixes as well as line-level and file-level disable actions.

Root cause

1. In run_external_rules(), the semantic is being taken to run the external JS plugin rules, leaving the former semantic inside the context host empty:
   

   oxc/crates/oxc_linter/src/lib.rs

   Line 539 in e23dccf

   let semantic = mem::take(ctx_host.semantic_mut());

2. The language server enables with_ignore_fixes to generate ignore fixes, but inside the add_ignore_fix(), it doesn't check the section_source_text.
3. The context host with the empty semantic passes the empty source text to the add_ignore_fix() as section_source_text, and the empty string just causes the crash.
   

   oxc/crates/oxc_linter/src/context/host.rs

   Lines 329 to 334 in e23dccf

   	if self.with_ignore_fixes {
   	let source_text = self.semantic().source_text();
   	for diagnostic in &mut diagnostics {
   	diagnostic.add_ignore_fix(self.current_sub_host().source_text_offset, source_text);
   	}
   	}

What changed

A new property source_text is added to the context sub host, which stores a reference to the real source text string. Even if the semantic is taken and becomes empty, the reference can still get the real string and make things work.

pub struct ContextSubHost<'a> {
    /// Semantic information about the file being linted, which includes scopes, symbols and AST nodes.
    /// See [`Semantic`].
    pub(super) semantic: Semantic<'a>,
    // ...
+   /// Stable source text for this script section
+   /// which remains available even after `semantic` is taken while running JS plugins.
+   pub(super) source_text: &'a str,
    /// The source text offset of the sub host
    pub(super) source_text_offset: u32,
}

And I added a new utility method to get the source_text from the context sub host.

#[inline]
pub fn source_text(&self) -> &'a str {
    self.current_sub_host().source_text()
}

When passing source text to add_ignore_fix(), just use the new source_text() method.

if self.with_ignore_fixes {
-   let source_text = self.semantic().source_text();
+   let source_text = self.source_text();
    for diagnostic in &mut diagnostics {
        diagnostic.add_ignore_fix(self.current_sub_host().source_text_offset, source_text);
    }
}
// (the same as other occurs

Also, I added the necessary check for the section_source_text in add_ignore_fix().

Notes

This is my first contribution to oxc project. Thanks for reviewing!

[codspeed-hq]

Merging this PR will not alter performance

✅ 5 untouched benchmarks
⏩ 71 skipped benchmarks¹

---

_{Comparing NriotHrreion:fix/25278 (abc586e) with main (e23dccf)}

Footnotes

1. 71 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[Sysix]

LGTM! Thank you.

@camc314 did not find a better way, waiting for your feedback :)

[jesse-kaufman]

Thank you!!