fix(commonjs): recognize named export

[rtritto]

Rollup Plugin Name: @rollup/plugin-commonjs

This PR contains:

• bugfix
• feature
• refactor
• documentation
• other

Are tests included?

• yes (bugfixes and features will not be merged without tests)
• no

Breaking Changes?

• yes (breaking changes will not be merged unless absolutely necessary)
• no

If yes, then include "BREAKING CHANGES:" in the first commit message body, followed by a description of what is breaking.

List any relevant issue numbers: #1678

Description

Add the analyze export lexer for named export that allows to recognize exports like:

// foo/index.js
Object.defineProperty(exports, "foo", { enumerable: true, get: function () { return 123; } });

[shellscape]

@rtritto looks like CI is failing on prettier

[charliecreates]

I reviewed the diff + CI + the context in #1678. Using cjs-module-lexer to augment named export detection (e.g. Object.defineProperty(exports, "foo", ...)) makes sense and matches what was discussed in the issue, but I don’t think this is merge-ready yet.

MUST fix (before merge)

1. CI is currently failing prettier:check (it flags packages/commonjs/src/analyze-exports-lexer.js). Please run Prettier and push the formatted result until checks are green.
2. Please add tests for the new named-export detection. At minimum, cover Object.defineProperty(exports, "foo", { ... }) and assert import { foo } from ./cjs works. (The PR template calls out that bugfixes/features won’t be merged without tests.)
3. Avoid console.warn(...) in this code path. If the lexer fails on a file, this could spam user builds. Prefer routing warnings through Rollup’s plugin context (e.g. pass this.warn into analyzeExports) or otherwise make it opt-in.
4. Revisit the lexer failure fallback: returning hasDefaultExport: true when parsing fails can flip meta.commonjs.hasDefaultExport and change interop semantics. Prefer returning hasDefaultExport: false/undefined on failure, and only updating commonjsMeta.hasDefaultExport when the lexer succeeded.

IMPROVEMENTS (non-blocking)
5. lexerReexports / resolveReexports(...) are parsed/stored but don’t appear to be consumed yet. Either wire this into the actual export generation logic, or drop it for now to keep the change focused.
6. Perf: this adds an additional parse pass for each CJS module (AST scan + lexer parse). If it ends up showing up in real-world graphs, consider only running the lexer when the AST analysis can’t confidently determine exports, or cache results more aggressively.

[rtritto]

@shellscape thanks for reply
Can you continue this PR?