vendor: add Box3D support for WebAssembly
Generate the WASM object directly from the existing build script so vendor binaries stay out of source control while JS target checks remain reproducible.
The broad VS-style `x86/` build-artifact rule was shadowing the re-housed
core/rexcode/isa/x86 source package (new files needed `git add -f`), and the
stale `core/rexcode/*/tables/*.bin` un-ignore no longer matched the deeper
isa/<arch>/tables path. Retarget both to isa/: allow the directory tree and
every arch's committed table blobs, while stray *.bin/*.obj/*.exe build
output inside it stays ignored.
Each ISA's hand-written ENCODING_TABLE (the single source of truth) now lives
in a per-arch tablegen/ metaprogram that flattens it and serializes committed
binary blobs; the library #loads those into @(rodata) at compile time rather
than compiling a table body. No arch keeps encoding_table.odin or
decoding_tables.odin -- only a generated tables.odin loader and tables/*.bin.
* Two-stage, type-checked pipeline: tablegen Stage A emits human-readable
generated Odin, which compiles and serializes the blobs in Stage B.
* encode() goes through encoding_forms(m); decoders are unchanged apart from
x86's flattened 2-D index. Decode tables are byte-identical to the old ones.
* build.lua: a LuaJIT driver for the metaprograms, validations, and tests,
with cross-platform gating and a clear report.
* Docs refreshed; the obsolete forward-looking plan in cross_arch_design.md
trimmed to what was actually built.
* Attribution headers added to all rexcode source files; the generators emit
them so generated files keep them.
All of our crypto is modern now unless exiled to the legacy sub-package,
so move the test cases for the currently un-unified algorithms into the
main test driver file, and rename the benchmark driver to reflect
reality.
- Introduce new `Path` type and an array of build paths on the build context.
- Resolve input and output paths/files early (before parsing).
- Error early if inputs are missing or outputs are directories.
- Plumb new file path generation into linker stage instead of its adhoc method.
TODO:
- Remove more adhoc file path generation in parser and linker stage.
- Make intermediate object file generation use new path system.
- Round out and robustify Path helper functions.
