git-mv the 10 foreign-named example families to extern/runtime-class names + update
every #import/#include/#source ref, stale comment ref, and the 1172 stderr snapshot
(path + 'extern symbol' message). Renames: 0729…-foreign→…-extern, 1172-diagnostics-
foreign-symbol-conflict→…-extern-symbol-conflict, 1205/1207 ffi-foreign-global→
ffi-extern-global, 1216/1217 ffi-…-foreign-(in-method|result-chain)→…-extern-…,
1219-ffi-foreign→1219-ffi-extern, 1306 objc-foreign-class-chained→objc-runtime-class-
chained, 1318 objc-property-foreign→objc-property-extern-class. DEDUP: deleted
1218-ffi-foreign-cvariadic (identical to 1229-ffi-extern-cvariadic; updated 1229's
twin ref) + the orphaned 1620 dir. Also purged editors/vscode tmLanguage (#foreign
dropped from the directive highlighter) + 1220.h/issues-0030.sx comment refs. Suite
green (644 corpus / 443 unit, 0 failed).
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.
Clear the examples/issue-* namespace (new layout keeps open-issue repros under
issues/, co-located with their .md). Two legacy files:
- issue-0030 was a feature-request placeholder (trivial main, no real test).
`extern G : T;` cross-file sx globals are still unimplemented (parse error),
so it's an open feature request: issues/0030-extern-global-declarations.{md,sx}.
- issue-0019 was a broken/superseded multi-file fixture (relative imports, not
runnable from root; the non-transitive-#import scenario is covered by the
passing 0706-modules-import-non-transitive). Moved to
issues/0019-import-non-transitive-c-scope/ with a status note; safe to delete.
Suite unchanged: 324 passed.