fix(codegen): #678 — re-export rename resolves to origin export name

[proggeramlug]

Summary

Closes the symbol-name-mismatch path of #678. When a consumer imports a name that traverses a re-export rename (import { Box } from \"ink\" where ink/build/index.js does export { default as Box } from './components/Box.js'), the codegen was forming the cross-module extern as perry_fn_<components_Box_js>__Box. The origin module emits the symbol under its own export name (default), so the linker failed with Undefined symbols: _perry_fn_..._Box.

Every compile-package shaped as export { default as <Name> } from \"./<Name>.js\" (ink components, hono adapters, drizzle subpackages, react sub-bundles, ...) hit this on any named import. The original issue's hypothesis pointed at V8-fallback demotion, but reduction to a single-package fixture shows the actual root cause is the lost rename across the re-export hop, not the V8 fallback path.

Root cause

all_module_exports[ink/index] carried \"Box\" → components/Box.js path but not the second piece of information needed — what name does Box.js export it under?. Every codegen call/wrapper/getter site that built perry_fn_<src>__<suffix> reused the consumer's imported name (Box) verbatim. The origin module emits the symbol under its own local name (default, because Box.js does const Box = ...; export default Box).

Fix approach

Track origin-name alongside origin-path across re-export chains. Threaded through end-to-end:

1. HIR-to-driver: new parallel map all_module_export_origin_names: BTreeMap<String, BTreeMap<String, String>> populated alongside all_module_exports during the export propagation loop. Sparse — only populated when origin_name differs from export_name. ReExport, Named, ExportAll, and NamespaceReExport branches all walk one extra hop to surface the deepest origin name through any chain depth.

2. Driver-to-codegen: new CompileOptions::import_function_origin_names field, copied into CrossModuleCtx, exposed on FnCtx. Cache key in object_cache.rs includes it so re-shape changes invalidate cached .o.

3. Codegen sites: new import_origin_suffix(map, name) helper returns the override-or-identity suffix. Every perry_fn_<src>__<name> construction site routes through it — lower_call.rs (direct extern call + namespace member call), expr.rs (ExternFuncRef value path, getter path for imported vars, namespace static method dispatch, property access on imported namespace), codegen.rs (FuncRef-as-value wrapper target).

4. var-vs-function classification: the imported_vars lookup now probes BOTH (origin, exported_name) AND (origin, origin_name) so a const X = ...; export default X re-exported as a different name still routes through the closure-getter call path instead of a direct function call.

Validation

• New regression fixture test-files/test_issue_678_reexport_default.ts + test-files/fixtures/issue_678_pkg/ covers three shapes (default-as-rename of const closure, default-as-rename of function decl, named-as-rename of function decl). Byte-for-byte parity with `node --experimental-strip-types`.
• `cargo test --release -p perry -p perry-codegen` — 157 + 29 tests pass.
• `/tmp/run_gap_tests.sh` — 34/36, same two pre-existing failures (`test_gap_console_methods`, `test_gap_regexp_advanced` — both in CLAUDE.md's known-categorical-gaps list).
• Existing `test_issue_310_namespace_reexport.ts` still passes (ExportAll / NamespaceReExport branches still work).
• The minimal ink repro from Linker: unresolved _perry_fn_..._render for V8-fallback modules referenced from main #678 now resolves Box / render correctly; remaining link failures in that repro (Text — `export default function`-body not lowered, react.development.js compile error in a closure, ink/devtools namespace global) are pre-existing bugs in unrelated code paths, not addressed here.

Test plan

• cargo test workspace (excluding cross-host UI crates per CLAUDE.md)
• gap suite — 34/36 (unchanged from baseline)
• new regression fixture parity-checks vs Node
• issue perry compile silently produces wrong output when import resolves through namespace re-export (export * as X from ...) #310 regression test still passes
• CI: `lint`, `cargo-test`, `parity`, `compile-smoke`, `api-docs-drift`, `security-audit`