The lowerCall namespace branch routed alias.fn() through the global
qualified registration (first-wins) at any import depth, and through the
global last-wins bare map for comptime/generic members. Plain-identifier
alias roots now resolve via the carry-aware namespaceAliasVerdict:
- visible alias (own edge or ONE flat hop): the member dispatches the
TARGET module's own fn (namespaceFnMember + fd-keyed bareAuthorFuncId),
so two modules' same-named aliases each call their own target.
- two direct flat imports carrying the alias to distinct targets:
loud ambiguity diagnostic.
- alias only reachable beyond one hop: "namespace 'X' is not visible".
- foreign / builtin / #compiler members keep the literal-symbol path.
Regressions: examples 0832 (two-hop), 0833 (carried collision),
0834 (own-target pin / first-wins repair).
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