Adds the pieces a toolchain-free joltc needs to compile apps with no external
Chez or cc:
- host/chez/java/io.ss: register-embedded-bytes!/jolt-embedded-bytes,
read-file-bytes, jolt-spill-embedded!, jolt-append-payload! (frames an app
boot onto the stub as [stub][boot][len:le64]["JOLTBOOT"]), and jolt-chmod-755
via load-shared-object #f (no subprocess).
- host/chez/stub/launcher.c: a native stub that locates its own executable,
reads the trailing frame, and hands the appended boot to the Chez kernel.
- host/chez/loader.ss: resolve-on-roots consults the embedded source store before
disk; ldr-read-source reads baked source. Dev (empty store) is unaffected.
- host/chez/build.ss: build-binary step 4 splits into build-self-contained
(in-process compile-file/make-boot-file with the system error restored, then
append the boot to a copy of the embedded stub) and build-with-cc (the existing
dev path). The self-contained path is taken only when the stub is embedded.
The legacy cc path is unchanged behaviorally; make buildsmoke still passes.
0420cd4d79