issues: file 0114 — namespace aliases leak transitively, collide first-wins

Found while probing the alias-carry design for the stdlib restructure
(plan in current/PLAN-STDLIB.md): qualified members register globally
with no per-importer gate, so an alias is usable any number of flat
hops away, and same-name registrations silently first-win. The carry
rule's one-level + ambiguity semantics fix both; repro and fix shape
in the issue.

issues/0114-namespace-alias-transitive-first-wins.md

@@ -0,0 +1,61 @@
+# 0114 — namespace aliases leak transitively and collide first-wins, silently
+
+**Symptom.** A namespace alias (`t :: #import "target.sx";`) declared in module
+B is usable from ANY module whose import closure reaches B — at any depth, flat
+or not — and when two modules register the same qualified name (`t.helper`),
+the first registration silently wins (`registerQualifiedFn`:
+`if contains return`). Expected (the approved carry design, session 72f): an
+alias is visible one level deep — in the declaring module and in its DIRECT
+flat importers — with own-wins / ambiguity-diagnostic collision semantics,
+mirroring ordinary declarations.
+
+This is the alias-side sibling of issue 0106 (bare-name over-permissiveness),
+plus a REJECTED-PATTERNS silent first-wins.
+
+## Reproduction
+
+```sx
+// target.sx
+helper :: () -> s64 { 7 }
+```
+```sx
+// facade.sx
+t :: #import "target.sx";
+```
+```sx
+// facade2.sx
+#import "facade.sx";
+```
+```sx
+// main.sx
+#import "modules/std.sx";
+#import "facade2.sx";          // TWO flat hops from the alias declaration
+main :: () { print("{}\n", t.helper()); }
+```
+
+- **Observed**: prints `7` — the alias rides two flat hops.
+- **Expected**: `'t' is not visible` (one-level carry; `facade2.sx` would need
+  to re-alias or flat-import `facade.sx`'s surface deliberately).
+
+Collision face: two modules each declaring `t :: #import` of DIFFERENT
+targets, both flat-imported by main — first-lowered wins silently.
+
+## Suspected area / fix shape
+
+Qualified members are registered GLOBALLY (`fn_ast_map["t.helper"]`,
+`registerQualifiedFn` in src/ir/lower/decl.zig ~1912) with no per-importer
+gate; `lowerCall`'s namespace path (src/ir/lower/call.zig ~687) and the
+comptime field-access path consult only that global map. Meanwhile
+`nominal.zig`'s `qualifiedStructTemplate`/`qualifiedMemberMissing` use STRICT
+per-file `namespace_edges` — so carried aliases are inconsistently
+over-visible for plain/comptime fns and under-visible for generic structs
+(and `alias.Type.method` heads — see PLAN-STDLIB).
+
+Fix shape: one carry-aware resolver on Lowering —
+`resolveNamespaceAlias(alias) → {own | carried(target) | ambiguous | none}`
+walking own `namespace_edges[from]` first, then the DIRECT
+`flat_import_graph[from]` targets' edges (one level; ≥2 distinct targets →
+diagnostic). Route every `ns.member` consumer through it: the global
+qualified-name paths gain the gate, the strict nominal/type paths gain the
+carry. See `current/PLAN-STDLIB.md` for the full design and the std.sx
+restructure that depends on it.