[codex] Harden route transforms and dev lifecycle

[ScriptedAlchemy]

Summary

• harden route export pruning and component wrapping for PR Add React Router plugin performance optimizations #39, including TypeScript runtime syntax, comments, named default classes, source re-exports, type exports, and lowercase JSX member imports
• isolate parallel route transform worker state by task/environment, cap/gate worker usage, and close pending work explicitly
• fix manifest emit error propagation, production source map handling, prerender default concurrency, and route topology watcher lifecycle coverage

Context

Stacked on #39 (perf/bundling-performance) in response to Matthew Davis's review notes and patch. I also cloned and indexed remix-run/react-router under /home/zack/projects/react-router; TraceDecay located the comparable Vite implementation at packages/react-router-dev/vite/remove-exports.ts, which I used as the main parity reference.

Validation

• git apply --check /home/zack/Downloads/0001-fix-harden-route-transforms-and-dev-lifecycle.patch
• pnpm test:core
• pnpm build
• pnpm format:check
• git diff --check HEAD^..HEAD
• pnpm --filter default-template test:e2e -- dev-route-watch.test.ts

Notes

This is still a large corrective patch. It addresses the concrete P1 regressions from the review, but it does not fully split #39 into the longer ideal stack described in the review file.

[pkg-pr-new]

Open in StackBlitz

pnpm add https://pkg.pr.new/rsbuild-plugin-react-router@933962d

commit: 933962d

[github-actions]

Benchmark Results

Compared PR head 933962d against base 06ae3db.

Total median wall time: 20.35s -> 9.40s (-53.8%, 2.16x speedup)

Benchmark	Base	Head	Delta	Speedup	Head RSS p95
synthetic-256-sourcemaps	3.59s	2.31s	-35.7%	1.56x	413 MB
synthetic-256-spa	8.46s	2.25s	-73.4%	3.76x	401 MB
synthetic-256-ssr-esm	3.59s	2.21s	-38.6%	1.63x	398 MB
synthetic-256-ssr-esm-split	4.70s	2.64s	-43.9%	1.78x	412 MB

Profile: default; iterations: 5; warmup: 1.
Workflow run

[chatgpt-codex-connector]

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