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.
Issue 0095: a typed local/param/field silently TRUNCATED a float initializer
to an integer annotation (`y : s64 = 1.5` → 1) with no diagnostic. Agra ruled
the UNIFIED rule (Option B): an implicit float→int in a typed binding behaves
like the array-dimension rule —
- an INTEGRAL compile-time float FOLDS to its int (`4.0` → 4, `-2.0` → -2);
- a NON-integral float is a COMPILE ERROR (`1.5`, `4.5`);
- explicit `xx` / `cast(T)` ALWAYS truncates (the escape hatch).
Applied consistently to typed local / param-default / field-default, typed
module CONST, and array dim — all reusing the single
`program_index.floatToIntExact` / `evalConstIntExpr` facility (no second
integral check).
- `Builder.constFloatInfo` reads a compile-time `const_float` back from its
Ref (value + span).
- `coerceToType` is now the IMPLICIT path: its `.float_to_int` arm folds an
integral const-float to `constInt`, else emits the narrowing diagnostic.
`coerceExplicit` is the raw truncating path; `xx` (lowerXX) and `cast(T)`
route through it so the escape still truncates.
- Field-default lowering (struct-literal pad, named-field default,
buildDefaultValue) now coerces the default to the field type at the IR level
(was silently bit-coerced by emitStructInit).
- Const path: `typedConstInitFits` accepts an integral float (literal or a
`M + 2.0`-style expression folding via `evalComptimeInt`); `emitModuleConst`
/ `constExprValue` / `globalInitValue` fold an integral float to its int and
reject a non-integral one — relaxing F0.7's blanket float rejection.
Tests: examples/0168 (positive: local/field/param/const fold, xx/cast
truncate), examples/1146 (negative: local/param/field error), integral-float
const cases added to examples/0162; non-integral const cases in 1143 stay
errors. specs.md + readme.md document the unified rule, cross-referencing the
array-dim rule. issues/0095 marked RESOLVED.
