fix(parser): require a string source after export ... from (#26389)

Named exports must have a string literal module source once `from` is present. The parser previously combined consuming `from` with checking whether the next token was a literal:

```rust
if self.eat(Kind::From) && self.cur_kind().is_literal()
```

When the next token was not a literal, `from` had already been consumed, but parsing fell back to a local export. This incorrectly accepted `export {} from;`, `export {} from` at EOF, and this input:

```js
export {} from
foo();
```

In the last case, the newline allowed automatic semicolon insertion, so the parser accepted a local empty export followed by `foo()` despite the incomplete `from` clause.

Remove the literal-kind guard so consuming `from` always leads to `parse_literal_string()`. That helper already requires a string literal and handles malformed input through the existing parser diagnostics. A missing source now produces a syntax error instead of becoming a local export, while unterminated strings and comments retain the standard lexer diagnostics.

Valid local exports such as `export { foo };` and re-exports such as `export { foo } from "./module.js";` keep their existing behavior, including a module source placed on the next line.

crates/oxc_parser/src/js/module.rs

@@ -560,7 +560,7 @@ impl<'a, C: Config> ParserImpl<'a, C> {
             })
         });
         self.expect(Kind::RCurly);
-        let (source, with_clause) = if self.eat(Kind::From) && self.cur_kind().is_literal() {
+        let (source, with_clause) = if self.eat(Kind::From) {
             let source = self.parse_literal_string();
             (Some(source), self.parse_import_attributes())
         } else {

tasks/coverage/misc/fail/export-from-missing-source-eof.js

@@ -0,0 +1 @@
+export {} from

tasks/coverage/misc/fail/export-from-missing-source-newline.js

@@ -0,0 +1,2 @@
+export {} from
+foo();

tasks/coverage/misc/fail/export-from-missing-source-semicolon.js

@@ -0,0 +1 @@
+export {} from;

tasks/coverage/misc/fail/export-from-prior-lexer-error.js

@@ -0,0 +1 @@
+export { "\xG" as foo } from

tasks/coverage/misc/fail/export-from-unterminated-comment.js

@@ -0,0 +1 @@
+export {} from /*

tasks/coverage/misc/fail/export-from-unterminated-source.js

@@ -0,0 +1 @@
+export {} from "

tasks/coverage/snapshots/lexer_misc.snap

@@ -1,3 +1,3 @@
 lexer_misc Summary:
-AST Parsed     : 255/255 (100.00%)
-Positive Passed: 255/255 (100.00%)
+AST Parsed     : 261/261 (100.00%)
+Positive Passed: 261/261 (100.00%)

tasks/coverage/snapshots/parser_babel.snap

@@ -9916,12 +9916,11 @@ Expect to Parse: tasks/coverage/babel/packages/babel-parser/test/fixtures/typesc
  1 │ import { foo, bar }
    ╰────
 
-  × Expected a semicolon or an implicit semicolon after a statement, but found none
-   ╭─[babel/packages/babel-parser/test/fixtures/esprima/es2015-import-declaration/invalid-import-module-specifier/input.js:1:18]
+  × Unexpected token
+   ╭─[babel/packages/babel-parser/test/fixtures/esprima/es2015-import-declaration/invalid-import-module-specifier/input.js:1:19]
  1 │ export {foo} from bar
-   ·                  ▲
+   ·                   ───
    ╰────
-  help: Try inserting a semicolon here
 
   × Expected `from` but found `,`
    ╭─[babel/packages/babel-parser/test/fixtures/esprima/es2015-import-declaration/invalid-import-named-after-named/input.js:1:13]

tasks/coverage/snapshots/parser_misc.snap

@@ -1,7 +1,7 @@
 parser_misc Summary:
 AST Parsed     : 84/84 (100.00%)
 Positive Passed: 84/84 (100.00%)
-Negative Passed: 171/171 (100.00%)
+Negative Passed: 177/177 (100.00%)
 
   × Cannot assign to 'arguments' in strict mode
    ╭─[misc/fail/arguments-eval-ambient.ts:2:13]
@@ -341,6 +341,42 @@ Negative Passed: 171/171 (100.00%)
    ╰────
   help: If you want to use `export =`, remove other `export`s and put all of them to the right hand value of `export =`. If you want to use `export`s, remove `export =` statement.
 
+  × Unexpected token
+   ╭─[misc/fail/export-from-missing-source-eof.js:2:1]
+ 1 │ export {} from
+   ╰────
+
+  × Unexpected token
+   ╭─[misc/fail/export-from-missing-source-newline.js:2:1]
+ 1 │ export {} from
+ 2 │ foo();
+   · ───
+   ╰────
+
+  × Unexpected token
+   ╭─[misc/fail/export-from-missing-source-semicolon.js:1:15]
+ 1 │ export {} from;
+   ·               ─
+   ╰────
+
+  × Invalid escape sequence
+   ╭─[misc/fail/export-from-prior-lexer-error.js:1:11]
+ 1 │ export { "\xG" as foo } from
+   ·           ──
+   ╰────
+
+  × Unterminated multiline comment
+   ╭─[misc/fail/export-from-unterminated-comment.js:1:16]
+ 1 │ export {} from /*
+   ·                ───
+   ╰────
+
+  × Unterminated string
+   ╭─[misc/fail/export-from-unterminated-source.js:1:16]
+ 1 │ export {} from "
+   ·                ──
+   ╰────
+
   × HTML comments are not allowed in modules
    ╭─[misc/fail/html-comment-in-module.mjs:1:1]
  1 │ <!-- comment