fix(compile): #818 — recursively bundle transitive ESM imports for V8 fallback

[proggeramlug]

Summary

• __perry_js_bundle.js only contained the first JS module Perry landed on. Pure-ESM packages whose entry re-exports siblings (hono's dist/index.js → ./hono.js → ./hono-base.js → … ~20 submodules) shipped with one entry, dropping the rest. Compiled binaries still worked when their node_modules/ tree happened to sit next to them (V8 reads files off disk), but the realistic hono call path (app.fetch(req) running cross-thread) cascaded into rc=139 segfaults when those paths weren't co-located.
• The JS branch of collect_modules was a leaf: it pushed one entry to ctx.js_modules and bailed with the comment "V8 will handle that at runtime". The native TypeScript branch already recursed through cached_resolve_import; JS did not.
• Added collect_js_module_imports — a lightweight regex-based scanner that extracts static import / export ... from / string-literal import(...) specifiers, resolves each relative / absolute path via the existing resolve_with_extensions, and re-enters collect_modules for every result. Bare specifiers (react, @foo/bar) stay the entry walker's job since the top-level TS path already pulls package deps in via cached_resolve_import.

Validation

• hono@4.12.19 repro under /tmp/perry-hono/ (import { Hono } from 'hono'; const app = new Hono(); …):
  • Pre-fix: __perry_js_bundle.js contained 1 globalThis.__COMPILETS_MODULES[...] entry (dist/index.js).
  • Post-fix: bundle contains 24 entries — every dist/**/*.js reachable from index.js through the full re-export graph (compose.js, context.js, hono.js, hono-base.js, http-exception.js, request.js, request/constants.js, router.js, plus the router/{reg-exp,smart,trie}-router/*.js and utils/*.js subtrees).
  • Runtime output unchanged: object / function / function.
• Compile smoke (console.log("hello")) still works.
• cargo build --release -p perry-runtime -p perry-stdlib -p perry-jsruntime -p perry green.

Known next blocker (out of scope)

V8's ModuleLoader::load in crates/perry-jsruntime/src/modules.rs:464-538 still reads sources via std::fs::read_to_string(&path) and never consults the embedded __COMPILETS_MODULES map. So the binary still requires the node_modules/ tree at runtime — removing it after compile produces Cannot resolve module. Wiring the loader to prefer the embedded source (a small short-circuit at the top of load()) is a separate fix toward the wider "single self-contained binary for V8-fallback packages" goal also captured under #818.

Test plan

• CI green (lint, cargo-test, parity, compile-smoke, api-docs-drift, security-audit)
• Manual hono smoke: cd /tmp/perry-hono && perry test.ts -o out && ./out prints object / function / function
• Bundle contains > 1 module entry for hono (grep -c '^globalThis.__COMPILETS_MODULES\[' __perry_js_bundle.js == 24)