Surface rename of the signed integer family: s1..s64 become i1..i64
(u1..u64, usize, isize unchanged). 'string' keeps the s-prefix arm in
name classification; width parsing moves to the i-prefix arm next to
isize.
Internal TypeId tags follow the surface (.s8/.s16/.s32/.s64 ->
.i8/.i16/.i32/.i64), as do mono-key mangle fragments (ptr_i64,
tu_i64_bool) and all display/diagnostic formatting (i{d}).
Migrated in the same sweep: stdlib + examples + issue repros + FFI C
companions (shared symbol names like ffi_id_i64), expected
stdout/stderr/ir snapshots, specs.md, readme.md, CLAUDE.md/AGENTS.md,
implementation_plan.md, docs/, issue writeups. Vendored stb_image and
historical flow state left untouched.
zig build test: 426/426; examples suite: 595/595.
The issue-0076 reserved-type-name binding diagnostic only ran over main-file
decls, so an imported module (or the stdlib) could still declare `s2 := ...`
and reach lowering, where the address-of family loads the whole aggregate and
passes it by value to a `ptr` param — LLVM verifier abort.
Extend coverage to every compiled module: a dedicated `checkBindingNames` walk
(in semantic_diagnostics.zig) visits every var/`:=`/typed-local binding name and
function/lambda/struct-method parameter at any depth, with NO main-file filter,
descending the `namespace_decl` that a `mod :: #import` wraps so imported-module
decls are reached. It tracks each module's source_file (save/restore per node)
so the diagnostic renders against the imported module's text. Rejection still
defers to the parser's `Type.fromName` classifier; the unknown-type check (0064)
stays main-file-only. No lowering special-case; `.identifier`-only address-of
paths are unchanged.
Stdlib audit: the only reserved-name bindings under library/ were two `u1`
locals in ui/renderer.sx (UV coords) — renamed to u_min/u_max/v_min/v_max.
Regression test: examples/1120-diagnostics-imported-reserved-type-name.sx (+
companion mod.sx) — an imported `s2 := ...` now emits the clean diagnostic at
the import's declaration site (exit 1), not an LLVM abort.
Resolves issues 0076 (coverage extension) and 0077.
