07. Spec + grammar.ebnf sync

Goal

Sync the syntax SSOT (grammar.ebnf) + spec prose to the implemented feature. grammar.ebnf:286 type_def gains [ ":" trait_list ]; add trait_list = trait_ref { "," trait_ref } + trait_ref = type_path [ "(" assoc_bindings ")" ] (§6.1). Remove #derive from the grammar (§6.7).

Implementation Items

grammar.ebnf type_def + trait_list/trait_ref (§6.1); remove #derive production (§6.7)
/sync-grammar clean
spec 08-types.md / 08-traits.md + error codes (proposal §13); /sync-spec clean

Spec References

proposal §6, §13; compiler_repo/docs/ori_lang/v2026/spec/grammar.ebnf.

Intelligence Reconnaissance

Graph-grounded during BUG-06-005 investigation + the dual-source /tp-help consensus (bug-tracker/plans/BUG-06-005/section-02-fix-consensus.md): reviewers ran file-symbols / callers / callees / symbols over ori_parse/grammar/item, ori_ir/ast/items/types.rs, ori_types/check/registration, ori_fmt, ori_eval/derives, ori_llvm/codegen/derive_codegen. Per-section graph queries to be re-run at /review-plan pre-implementation gate. (2026-06-01)