test(application): symbol-graph lib tests red after single-row code edges (#2277)

[ScriptedAlchemy]

Eleven tracedecay-application lib tests fail on origin/master (e02eb55). They passed on 56839b9, before #2277 (perf(graph-db): store each code edge as one relation row) and #2271 landed; #2277's local proof did not run the application lib suite.

Reproduce:

cargo test -p tracedecay-application --lib primitives::symbol_graph_

Result: 466 passed; 11 failed. Failing tests:

• primitives::symbol_graph_ignored_dependency_tests::edge_cases::multiple_candidates_submit_only_the_first_canonical_scoped_row: candidate rows: Corrupt("code graph row file-record has the wrong type")
• ...edge_cases::same_generation_scheduler_success_is_typed_not_advanced
• ...edge_cases::stale_claim_finish_prevents_lazy_scheduler_mutation
• ...edge_cases::zero_symbol_and_import_candidates_complete_empty_without_a_scheduler
• ...exact_symbol_absent_scheduler_fails_closed_without_legacy_support_gap
• ...exact_symbol_generation_advance_returns_stale_retry_without_same_call_symbol: left: Unavailable, right: Stale
• ...exact_symbol_never_schedules_without_opt_in_or_after_a_positive_exact_match
• ...exact_symbol_scheduler_failures_remain_typed_and_never_become_support_gaps
• ...page_uses_the_verified_projection_freshness
• primitives::symbol_graph_implementation_tests::qualified_trait_selection_returns_only_its_stable_typed_implementors: simple typed implementation selection: ()
• primitives::symbol_graph_implementation_tests::simple_trait_selection_uses_every_typed_same_name_identity

The fixtures build code-graph rows in the pre-#2277 shape, and the projection reader now refuses them as a wrong-typed file record. Either the fixtures follow the new row format, or the reader regressed for these rows; the #2277 owner should decide which.

Found while landing the problem-detail follow-ups; that change does not touch the code graph.

[ScriptedAlchemy]

Same boundary, mcp_suite (cargo test -p tracedecay --features test-transport,test-helpers --test mcp_suite): five read-cost tests fail on e02eb55 and passed on 56839b9 (576/576 there).

• graph_query_test::relation_page_cost::a_callees_page_reads_its_own_rows_not_every_relation (page_cost(&first) == (11, 2, 210) no longer holds)
• graph_query_test::relation_page_cost::a_default_callees_page_resolves_dispatch_without_reading_every_callee
• graph_query_test::typed_evidence_trailers::typed_callees_carry_their_read_cost_on_the_envelope_and_the_trailer
• graph_query_test::typed_evidence_trailers::typed_callers_carry_their_read_cost
• test_map_test::test_map_reads_each_test_once_across_the_symbols_it_covers (attempt to subtract with overflow at test_map_test.rs:476)

They pin point-read and fan-out counts that #2277's one-row-per-edge storage changes; #2277's proof did not run mcp_suite.