* fix: preserve module URLs in the headless server bundle
* test: exercise structured chat on the packaged Node server
* test(orcad): run the packaged chat check from the desktop's server template
The chat check loaded the server bundle directly, so a desktop build missing its
server template still passed. Materialize the slot from the built template the way
the desktop does, and replace the fixed streaming pause with a test-owned
acknowledgement so the partial-reply assertion can't race.
* Connect the packaged chat test through a paired connection
Main now sends remote runtime requests over a paired connection rather than a
pairing offer, so the test converts the server's offer once when it is ready.