fix(app-router): ignore very dynamic requests during build analysis

[NathanDrake2406]

Overview

Field	Details
Goal	Match Next.js App Router build behaviour for very dynamic import(...) and require(...) calls.
Core change	Add a pre-transform that removes only requests with no static path part from build graph analysis.
Main boundary	Static or partly static requests still flow through existing Vite/CommonJS analysis. Fully dynamic requests remain runtime-only and fail only if executed.
Primary files	packages/vinext/src/plugins/ignore-dynamic-requests.ts, packages/vinext/src/index.ts, tests/build-optimization.test.ts
Expected impact	App Router page and route builds no longer fail on guarded require(dynamic) / import(dynamic) patterns that Next.js accepts.

Why

App Router production builds must separate graph-analysis inputs from code that is only meaningful at runtime. Next.js/Turbopack treats requests with no static known path part as "very dynamic" and, with ignore_dynamic_requests, avoids adding them to the module graph. Vinext violated that boundary because vite-plugin-commonjs tried to expand require(dynamic) as a static glob, causing a build-time failure even when the code was unreachable.

Area	Principle / invariant	What this PR changes
App Router build analysis	Very dynamic requests should not become required static graph edges.	Rewrites only require(...) calls that have no static request part to a runtime helper before CommonJS analysis.
Dynamic import(...)	Vite should not warn or analyze requests that Next.js treats as runtime-only.	Adds /* @vite-ignore */ only for imports with no static request part.
Compatibility	Analyzable requests must keep existing behaviour.	Leaves literals, non-empty templates, and expressions with static parts untouched.

What changed

Scenario	Before	After
require(dynamic) with no static path part	Build failed in vite-plugin-commonjs with an invalid dynamic import error.	Build succeeds and the request remains runtime-only.
import(dynamic) with no static path part	Vite attempted dynamic request analysis.	The import is marked with @vite-ignore.
require('./' + name) or import(./${name})	Existing static-part analysis path.	Unchanged.

Maintainer review path

1. packages/vinext/src/plugins/ignore-dynamic-requests.ts validates the request classification and transform boundaries.
2. packages/vinext/src/index.ts places the plugin immediately before vite-plugin-commonjs, which is the failing analyzer.
3. tests/build-optimization.test.ts ports the upstream dynamic-requests scenario at the production build boundary.

Validation

• vp test run tests/build-optimization.test.ts tests/cjs.test.ts
• vp check
• vp env exec --node 24 ./scripts/run-nextjs-deploy-suite.sh /Users/nathan/Projects/vinext/.refs/nextjs-v16.2.6 --retries 0 -c 1 --debug test/e2e/app-dir/dynamic-requests/dynamic-requests.test.ts
• Commit hook: formatting, lint/type checking, and knip

Risk / compatibility

• Public API impact: none.
• Runtime impact: only fully dynamic require(...) calls are redirected to a runtime helper that throws if executed, matching the intended runtime-only failure shape.
• Build output impact: static and partly static request expressions continue to use the existing analyzer path.
• Framework compatibility: intentionally follows Next.js/Turbopack's ignore_dynamic_requests behaviour for requests without a static known part.

Non-goals

• This PR does not implement Turbopack's broader handling for dynamic new URL, filesystem, or child process request patterns.
• This PR does not change the existing CommonJS transform for analyzable request expressions.

References

Reference	Why it matters
Next.js dynamic-requests e2e test	Upstream contract: guarded dynamic requests in pages and routes should not error.
Next.js ignore_dynamic_requests option	Documents the intended semantics for requests without a static known part.
Turbopack dynamic import(...) handling	Shows very dynamic imports become runtime dynamic expressions when ignored.
Turbopack dynamic require(...) handling	Shows very dynamic requires become runtime dynamic expressions when ignored.