fix: allow lexical import shadowing

docs/test-system-v2.md

@@ -598,7 +598,53 @@ precedence. Type-shaped arguments parsed for `size` and `align` must retain type
 checking when either spelling is instead an import binding; neither stage may
 fall into an internal expression-kind diagnostic.
 
-The same observer must exercise ordinary root and imported builds plus
+The adjacent focused dual-stage
+`lexical_import_bindings_shadow_normally` package observer, together with the
+tool-suite `paramshadow_lexical_bindings` fixture matrix, is the acceptance
+owner for ordinary lexical shadowing of an effective file-local package-name
+object. Together they require a selector before a later local to resolve to and
+consume the import, while the later spelling resolves to the closer parameter,
+`let`, tuple-let, ordinary-`for`/range, or match-arm binding. Nested blocks and
+loop exit restore the import; a parameter wins throughout its body;
+self-shadowing initializers retain the outer import until the local declaration
+point; and every annotated tuple type is checked before any tuple binder enters
+scope. Default, explicit, and builtin-spelled qualifiers follow the same rule.
+A local value, struct or pseudo-field, function-pointer field, or local
+enum/member collision must use the local receiver rather than recover the
+same-spelled import. Conversely, a shadowed dotted type or invalid scalar
+selector must reject as a local use without a checker/backend cascade. A
+selector-shaped local-only occurrence does not consume the import, so its
+unused diagnostic retains source-position precedence. Sibling source files
+retain independent import bindings and a separately selected legal import use
+remains effective. Blank, effective-`init`, and missing-target controls remain
+owned by their immediately adjacent focused observers and are explicit
+non-effects of this acceptance pair.
+
+This observer exercises raw-source and directory builds, imported dependencies,
+production reached by tests, same-package, external-test, and honest
+test-only sources, filtered execution, retained test execution, and later
+direct retained-binary execution. Cstage and WWstage must agree on status,
+stdout, normalized full stderr (including positioned diagnostic order) for
+build and test rejection, representative comparable semantic artifacts, every
+test role's public binary bytes, retained binary bytes, and valid runtime
+results. Its lifecycle matrix requires cold invalid requests to leave no public
+or retained product and an empty workdir; a warm valid-to-invalid unused-import
+transition whose source also contains an invalid local selector to preserve the
+prior public product and complete committed generation byte-for-byte; and
+restoration to recover ordinary exact-byte reuse with no `.new`, `.install`,
+`.wwtxn.*`, adjacent `.sepwork`, capture/result, or request-scratch residue. The
+rule changes neither source eligibility,
+package/import identity, direct graph edges, action/variant identity, init
+ordering, test process/state/fatal-abort topology, runtime/process ownership,
+publication transaction shape, persistence format, concurrency isolation,
+interruption handling, nor descendant cleanup; those boundaries retain their
+existing owners. Go has no range-loop `else` clause; that WW-only extension's
+pre-existing Cstage/WWstage scope difference is explicitly outside this
+pinned-Go observer, and each import-use prepass continues to mirror its own
+stage's live checker there.
+
+The `bare_import_bindings_require_selectors` observer must exercise ordinary
+root and imported builds plus
 production, same-package test, external-test, and honest test-only source
 roles. Cstage and WWstage must agree on status and normalized stdout/stderr,
 including diagnostic order and source position, and valid controls must produce