fix(codegen): preserve default import names in source maps (#28058)

Default imports with escaped identifiers (for example, `import s\u006furce from "./a.js"`) lose their original spelling from JS codegen source maps. The default-import printer records an unnamed mapping for the specifier instead of a named mapping for its local identifier.

Use the same named identifier mapping as the other import forms. Add regressions for default imports, type-only imports, and defaults combined with named or namespace imports; each compares code and complete source maps against Rust in both parenthesis modes.

Exposed by the TypeScript fixture update in #28057 and [this failed CI job](https://github.com/oxc-project/oxc/actions/runs/39690771786/job/119536110779). Stack: this fix targets `main`; #28057 targets this branch.

packages/codegen/src-js/print/module.ts

@@ -72,13 +72,12 @@ export function printImportDeclaration(node: ESTree.ImportDeclaration, state: St
         }
 
         printSpaceBeforeIdentifier(state);
-        writeWithMap(
+        writeWithMapNamed(
           state,
           specifier.local.name,
-          CAT_IDENT,
-          specifier.start,
-          specifier.end,
-          specifier,
+          specifier.local.start,
+          specifier.local.end,
+          specifier.local,
         );
 
         if (i === length - 1) write(state, " ", CAT_OTHER);

packages/codegen/test/source-maps.test.ts

@@ -94,6 +94,26 @@ describe("Rust conformance", () => {
       lang: "js" as const,
     },
     { name: "astral-new.js", code: "new 𐐀;", lang: "js" as const },
+    {
+      name: "escaped-default-import.js",
+      code: 'import s\\u006furce from "./a.js";',
+      lang: "js" as const,
+    },
+    {
+      name: "escaped-default-import.ts",
+      code: 'import type s\\u006furce from "./a.js";',
+      lang: "ts" as const,
+    },
+    {
+      name: "escaped-default-and-named-import.js",
+      code: 'import s\\u006furce, { value } from "./a.js";',
+      lang: "js" as const,
+    },
+    {
+      name: "escaped-default-and-namespace-import.js",
+      code: 'import s\\u006furce, * as ns from "./a.js";',
+      lang: "js" as const,
+    },
     {
       name: "large-line-gap.js",
       code: `\`${"\n".repeat(200)}\`;\nvalue;`,