Fix boost-module index redirect namespace

The [indices] table is keyed by namespace, but the member still declared
it as `boost` while the dependency moved to namespace `ZheFeng7110`.
Registration missed and resolution fell through to the published index:

  error: dependency 'ZheFeng7110.boost': no package found for exact selector

Key the redirect by the dependency's namespace so the checkout's
pkgs/z/ZheFeng7110.boost.lua is what gets tested.

Author: ZheFeng7110

tests/examples/boost-module/mcpp.toml

@@ -5,11 +5,13 @@
 # default lookup is exercised.
 #
 # Overrides the workspace-root redirect: root declares `compat`, this member
-# needs `boost`. A member-level [indices] REPLACES the inherited table rather
-# than merging with it, which keeps this to ONE project index repo — two repos
-# pointing at the same tree make every lookup ambiguous.
+# needs `ZheFeng7110`. The table is keyed by NAMESPACE, so the key must be the
+# dependency's namespace (`ZheFeng7110`), not the package name (`boost`). A
+# member-level [indices] REPLACES the inherited table rather than merging with
+# it, which keeps this to ONE project index repo — two repos pointing at the
+# same tree make every lookup ambiguous.
 [indices]
-boost = { path = "../../.." }
+ZheFeng7110 = { path = "../../.." }
 
 [package]
 name    = "boost-module-tests"