Adopt the modern-di integration kit

[lesnik512]

Summary

• Composes modern_di.integrations (shipped in modern-di 2.28.0) instead of hand-rolling the same logic — zero change to public API or test behavior.
• _DIMiddleware's isinstance-over-tuple connection dispatch is replaced by integrations.classify_connection; the manual try/finally around the child container is replaced by Container's own async with protocol.
• _FromDI/_parse_inject_params/_resolve_di_params are deleted; FromDI becomes a direct re-export of integrations.from_di; inject composes integrations.parse_markers/resolve_markers.
• pyproject.toml's modern-di floor bumped to >=2.28.0,<3.
• architecture/container-lifecycle.md, architecture/dependency-resolution.md, and architecture/glossary.md promoted to describe the new internals.

Design background: planning/changes/2026-07-13.01-adopt-integration-kit.md. This is the first of 13 planned adapter conversions across the modern-di ecosystem (starlette chosen first, per modern-di's own rollout plan, as the richest non-native-DI example).

Test plan

• just test-ci — 8 passed, 100% line coverage
• just lint-ci — ruff format/check, ty check, check-planning all clean
• No test file touched anywhere in this branch — the existing suite is the regression check, and it passed unmodified after every task
• Built via subagent-driven-development: 5 planned tasks, each with an independent spec+quality review; a whole-branch review before merge — verdict "Ready to merge: Yes"