fix(pkg): support worker-backed tools in single exe

pkg stores application files in a virtual filesystem, and its
worker_threads hook discovers worker entry points only when they are passed
as filesystem strings. Convert the code-runtime entry with fileURLToPath()
and return the workflow built entry as a string while retaining its
source-mode data URL bootstrap.

Emit worker entry bundles as CommonJS .cjs files. pkg executes a VFS-backed
string-path worker through Module._compile, so an ESM-only entry can be
present in the executable yet still fail when launched. Keep the public hosts
ESM, adapt worker startup accordingly, and align exports, package file lists,
workspace constraints, documentation, and built-worker tests with the actual
artifact format.

Expand the custom-config executable smoke to load the Code Mode and workflow
plugins and script real run_code and zero-agent workflow calls. Require both
tools to return 42 from workers launched inside the pkg VFS, turning worker
support from an asset-presence assumption into an end-to-end runtime
contract.

Update the implemented RFC and verification gates to describe and exercise
the supported built-worker path. This adds no tool or JSON-RPC protocol shape;
it fixes how existing worker-backed capabilities are located and executed in
the single-file distribution.

docs/rfc/implemented/architecture/2026-07-10-single-file-executable-sdk-runtime-distribution.md

@@ -58,11 +58,11 @@ The exe's "must be explicitly configured" hard semantic is unchanged; the zero-c
 
 ## Disposition of worker-style plugins
 
-`dsh-workflow-workerthread` and `dsh-code-runtime-worker` depend on on-disk sibling files via `new Worker(new URL('./worker.js', import.meta.url))`. PoC measurement: pkg's Worker patch intercepts **string paths only**; the URL-object form finds no file inside the VFS. The fix is already known (`fileURLToPath()` to a string), but this round's review decision is **do not verify, do not promise, do not handle**: they compile into the exe with the full set, and behavior when an external `cordis.yml` references them is undefined.
+`dsh-workflow-workerthread` and `dsh-code-runtime-worker` are supported inside the exe. Their built entries convert the sibling worker URL with `fileURLToPath()` and pass the resulting filesystem string to `Worker`, which is the form pkg's Worker hook resolves inside the VFS. The workflow engine keeps its data-URL bootstrap for unbuilt source execution; only its built sibling entry uses the filesystem string. The custom-config executable smoke loads both backends, invokes a real `run_code` call and a zero-agent `workflow` call, and requires each worker to return `42` from inside pkg's VFS.
 
 ## Testing
 
-The verification surface has three tiers. Mechanism tier: the measured conclusions for the `--sea` chain are embedded in the Decision sections (ESM dynamic import inside the VFS, single cordis instance, fail-loud config chain, `node:sqlite`, macOS ad-hoc signing runs). SDK tier: the complete keyless pytest suite covers the client protocol against a fake runtime peer, subprocess cleanup, absolute cwd propagation, dual-carrier launch, and carrier resolution; root CI runs it on Python 3.10. End-to-end tier: every platform build completes a turn against a mock endpoint through the default SDK path, a custom config, and the direct binary protocol, with final text and JSONL checked; its platform wheel is then installed in a clean venv and run without `runtime_bin`. The JSON-RPC protocol is not part of the ACP snapshot system, so there is no snapshot tier (an explicitly named gap, not an oversight).
+The verification surface has three tiers. Mechanism tier: the measured conclusions for the `--sea` chain are embedded in the Decision sections (ESM dynamic import inside the VFS, single cordis instance, fail-loud config chain, `node:sqlite`, macOS ad-hoc signing runs). SDK tier: the complete keyless pytest suite covers the client protocol against a fake runtime peer, subprocess cleanup, absolute cwd propagation, dual-carrier launch, and carrier resolution; root CI runs it on Python 3.10. End-to-end tier: every platform build completes a turn against a mock endpoint through the default SDK path, a custom config, and the direct binary protocol, with final text and JSONL checked. The custom config additionally drives `run_code` and a zero-agent `workflow` through their real worker files inside the packaged VFS. Its platform wheel is then installed in a clean venv and run without `runtime_bin`. The JSON-RPC protocol is not part of the ACP snapshot system, so there is no snapshot tier (an explicitly named gap, not an oversight).
 
 Manual-driving caveat: the bin treats stdin EOF as "the client is gone" and disposes immediately, so a short-lived pipe aborts an in-flight turn — pipe-driven runs must keep stdin open until the turn ends.
 
@@ -82,4 +82,4 @@ Manual-driving caveat: the bin treats stdin EOF as "the client is gone" and disp
 
 **Bought**: zero-dependency single-file distribution on target platforms; plugin semantics strictly identical to running from source (the same real package tree, no transpilation, no registry); the serving surface, the plugin set, and the configuration all converge on two sources of truth — `cordis.yml` plus one dependency manifest; the exe and node carriers share one tree and one semantics, so development verification never waits for packaging; official Node binaries remove the patched-binary supply-chain concern.
 
-**Paid**: artifacts on the order of 174MB with source entering the blob as-is (no bytecode obfuscation; a closed-source distribution requirement needs a separate evaluation); pkg's VFS/module-hook layer remains community-maintained (the build script pins `@yao-pkg/pkg@6.21.0`; upgrading is an explicit change); `--sea` is one invocation per target (matching CI's one leg per platform; local multi-platform builds are serial); worker-style plugins have undefined behavior inside the exe.
+**Paid**: artifacts on the order of 174MB with source entering the blob as-is (no bytecode obfuscation; a closed-source distribution requirement needs a separate evaluation); pkg's VFS/module-hook layer remains community-maintained (the build script pins `@yao-pkg/pkg@6.21.0`; upgrading is an explicit change); `--sea` is one invocation per target (matching CI's one leg per platform; local multi-platform builds are serial).