test(ir): pin canonical Place binding metadata blocker

[agourakis82]

Scope

Stacked on #973. This does not implement or allocate a canonical Place binder. It pins the first exact metadata-loss boundary and fails closed before any caller-supplied or synthesized type/layout/field identity can be mistaken for compiler authority.

Executable evidence

• active-load function route (module index, name) survives; this is not claimed as a durable DefId
• nominal module provenance is lost when TypeExpr.path lowers to module-less TypeEntry::TyNamed
• resolved callee/owner/field/ordinal evidence is not persisted past checker expression return
• first wrong physical choice remains field_idx_for_base_ref for a non-identifier base
• typed local controls: 42 in single-module and both imported permutations
• direct projection: declaration/import A then B returns 11; B then A returns 42
• witness supplies no Place ordinal/layout/type authority
• no parser/checker/lower/IR/SOIR/writer/backend/default-route file changed

Blocker

BLK-20260715-place-canonical-nominal-identity is classified, B1, compiler-semantics, E3.

Result: BLOCKED_REQUIRED_METADATA_NOT_EXPORTED_ON_ACTIVE_FIELD_PATH.

Missing: generation-bound root-binding receipt, module-qualified type identity, exact field identity, and target layout epoch. The next semantic step is a frozen receipt exported before the shared multi-module checker is freed. No name/hash/collection/source/import-order fallback is permitted.

Local gates

SOUC_BIN=/tmp/pr973-current-source-29419519269/madaros \
PLACE_CANONICAL_BINDING_EXPECTED_COMPILER_SHA256=7ad961849c398ba6dc709dd327f14f14405062bb12638d48374d8619a1ba8372 \
bash scripts/ci/place_canonical_binding_shadow_gate.sh

SOUC_BIN=/tmp/pr973-current-source-29419519269/madaros \
bash scripts/ci/place_ir_arena_v2_shadow_gate.sh

Both pass on the exact #973 current-source artifact. Orthogonal current-diff review: APPROVE. Legacy path intentionally kept unchanged. No fallback. No merge requested.

[agourakis82]

Canonical-binding blocker receipt at exact head 4c952e6ee7bcd0855f675fc662420c2fa507e19a:

PLACE_CANONICAL_BINDING_TRACE active_load_function_route=module_index_plus_name nominal_return_type=name_only field_identity=absent production_layout_identity=absent
PLACE_CANONICAL_BINDING_NOMINAL_LOSS boundary=checker_lower_named_type_mut detail=TypeExpr.path_to_moduleless_TypeEntry.TyNamed
PLACE_CANONICAL_BINDING_RECEIPT_LOSS boundary=checker_expression_return detail=callee_active_load_route,owner_struct,matched_field,ordinal_not_persisted first_wrong_choice=lower.field_idx_for_base_ref_non_ident
PLACE_CANONICAL_BINDING_DIFFERENTIAL single_module_typed_local=42 imported_typed_local_ab=42 imported_typed_local_ba=42 direct_call_a_then_b=11 direct_call_b_then_a=42 import_ab=11 import_ba=42 declaration_order_changes_result=true import_order_changes_result=true witness_place_authority_supplied=false legacy_fallback_observed=true
PLACE_CANONICAL_BINDING_BLOCKER Blocker-ID=BLK-20260715-place-canonical-nominal-identity Status=classified Severity=B1 Class=compiler-semantics Evidence-Level=E3 Result=BLOCKED_REQUIRED_METADATA_NOT_EXPORTED_ON_ACTIVE_FIELD_PATH Binder-Present=false Binder-Fallback-Used=not_applicable Missing=root_binding_receipt,module_qualified_type_identity,field_identity,target_layout_epoch

Compiler artifact was the exact source-fresh #973 artifact: size 107767984, SHA-256 7ad961849c398ba6dc709dd327f14f14405062bb12638d48374d8619a1ba8372. Both the new blocker gate and the inherited Place structural gate passed. Orthogonal current-diff review: APPROVE.

Boundary: this receipt proves why allocation must stop. It does not claim canonical binding, parity, a durable DefId, nested projection coverage, layout-epoch availability, backend wiring, or a semantic fix. Default parser/checker/lower/IR/SOIR/writer/backend surfaces are unchanged. No merge requested.

[github-actions]

CI Watch: GREEN

Run: 29422955946
Head: 4c952e6ee7bc
Failed jobs: none

Next action: All selected checks passed; ready for merge subject to repository policy.

This watcher observes CI only. It cannot merge, edit code, or decide scientific semantics.

[agourakis82]

CI watcher terminal receipt: GREEN.

• exact head: 4c952e6ee7bcd0855f675fc662420c2fa507e19a
• PR remains OPEN + DRAFT
• stacked base: codex/place-ir-arena-v2-shadow-20260715
• 12 successful checks
• 2 skipped automation checks
• 0 pending
• 0 failing/cancelled
• CI Decision: success
• lane-caused failure: n/a
• no edit and no merge by watcher

Run: https://github.com/Sounio-lang/sounio/actions/runs/29422955946
Decision: https://github.com/Sounio-lang/sounio/actions/runs/29422955946/job/87380782012

This remote green proves the blocker-only diff is repository-compatible. It does not upgrade BLOCKED_REQUIRED_METADATA_NOT_EXPORTED_ON_ACTIVE_FIELD_PATH into a canonical binder claim.

[agourakis82]

Exact-head remote artifact follow-up:

• CI run: https://github.com/Sounio-lang/sounio/actions/runs/29422955946
• artifact: madaros-current-source-f64-lowering (8346222143)
• downloaded ELF: 107767984 bytes
• SHA-256: 7ad961849c398ba6dc709dd327f14f14405062bb12638d48374d8619a1ba8372
• place_canonical_binding_shadow_gate.sh: PASS against downloaded exact-head artifact
• inherited place_ir_arena_v2_shadow_gate.sh: PASS against the same artifact

The compiler ELF hash matches the #973 artifact because #979 changes only the blocker gate and witnesses; this run nevertheless proves artifact provenance at exact head 4c952e6ee7bcd0855f675fc662420c2fa507e19a.