compat: undefined default-wrapper symbols for re-exported barrel modules (nestjs link wall)

[proggeramlug]

Split out from #1021. The async-lowering architectural problem #1021 was opened for is fixed (#1041); express/hono/fastify in-process self-fetch all pass on v0.5.1152. The remaining nestjs fixture is a different problem — a native-link wall, not async lowering — so it gets its own issue.

Symptom

tests/release/packages/nestjs-hello now resolves deps and compiles past the earlier CommonJS/buffer walls, reaches native linking, and fails on undefined default-wrapper symbols for modules that are import barrels / type-only / interface re-export surfaces:

undefined reference to `__perry_wrap_perry_fn_node_modules_rxjs_src_index_ts__default'
undefined reference to `perry_fn_node_modules_rxjs_src_index_ts__default'
undefined reference to `perry_fn_node_modules_rxjs_src_operators_index_ts__default'
undefined reference to `perry_fn_node_modules_uid_dist_index_mjs__default'
undefined reference to `__perry_wrap_perry_fn_node_modules__nestjs_core_router_interfaces_routes_interface_js__default'
undefined reference to `__perry_wrap_perry_fn_node_modules__nestjs_platform_express_interfaces_nest_express_application_interface_js__default'

Call sites emit default-call / default-wrapper references for these modules, but no object file defines the matching symbols because the module is a barrel/type-only re-export with no concrete default function definition.

What's needed

Make default-import / default-call lowering either:

1. follow re-exported module surfaces back to the concrete default binding, or
2. avoid emitting callable default references for type-only / interface barrels.

Reproduce

cd tests/release/packages/nestjs-hello
npm install
../../../../target/release/perry entry.ts -o ./out

The fixture's fixture.sh reports SKIP while WALLS.md is present, so the release sweep records the gap without going red. See tests/release/packages/nestjs-hello/WALLS.md (Wall 1) for the running provenance.

Prior work

• fix(async): #1021 async-closure state machine + #1029 re-invocation idempotency #1041 — async-closure state machine (fixed the compat: async lowering blocks self-fetch (express/fastify/nestjs/hono) #1021 self-fetch deadlock)
• [codex] fix re-exported class method prefixes #4274 — canonicalized re-exported class method prefixes through the defining file path (a sibling barrel-symbol fix on the class side)

[proggeramlug]

Resolved by #4885 (merged). The nestjs-hello fixture now compiles and links end-to-end — all the …__default / __perry_wrap_perry_fn_…__default barrel symbols and the perry_fn_…_common_index_js__Controller-family named-import symbols resolve.

What landed:

• Default imports of modules with no default export (rxjs src/index.ts, uid dist/index.mjs) now bind the module namespace (Node require(esm) semantics) instead of a phantom callable.
• __exportStar(require("./x"), exports) in CJS-wrapped sources also emits a real export * from './x', so multi-level tsc barrels resolve named imports to the defining module.
• tsc type-only modules (Object.defineProperty(exports, "__esModule", …)-only) are detected as CJS.
• export * propagation no longer leaks default across hops; TS constructor overload signatures no longer count as duplicate constructors (rxjs Notification).

The fixture still SKIPs on the next (different) wall: .prototype of a capturing class expression (ClassExprFresh lowering) reads undefined, so tslib's __decorate throws Cannot convert undefined or null to object during @nestjs/common/services/logger.service.js init. Minimal repro and analysis are in tests/release/packages/nestjs-hello/WALLS.md (Wall 2) — that's a separate runtime-semantics bug, not a link issue, so it should get its own issue.