docs: guidance for future Claude Code instances, as CLAUDE.md

[btravers]

What

Adds a CLAUDE.md at the repo root — the file Claude Code loads as repository guidance.

Contents

• Commands: the six-command gate from CONTRIBUTING.md (matching CI), how to run a single test file or test by name inside packages/di, type-level tests, and the commitlint/changeset conventions.
• Architecture: a file-by-file map of packages/di/src with the load-bearing design points — nominal port identity via unexported symbol brands, the mutually exclusive construction arms, the phantom-channel variance rule, the arity-based UNSATISFIED DEPENDENCIES gate, and WiringDefect throws routed to unthrown's Defect channel — plus the *.test-d.ts setup, the dual-TypeScript-version emit check, and the examples-as-tests arrangement.
• Binding rules: source comments are regression guards, unthrown/* lint rules are binding, one name per concept.

No changeset: internal tooling documentation, no API or behaviour impact.

[Copilot]

Pull request overview

Adds a new root-level CLAUDE.md intended to be loaded by Claude Code as repository guidance, documenting the repo’s command “gate”, architecture map of packages/di/src, and a few binding design rules so future automated/codegen passes match established project constraints.

Changes:

• Introduces CLAUDE.md with contributor workflow commands (format/lint/typecheck/test/knip/build) and scoping examples.
• Documents the DI container’s architecture and key type-level/runtime invariants (ports/providers/modules/build pipeline, scope lifecycle, type-level tests).
• Captures binding design rules (comments as regression guards, errors-as-values discipline, “one name per concept”).

---

💡 Add a code-review agent skill or configure MCP servers for context-aware, tailored reviews. Learn more in the docs.