fix: patch development dependencies and share project instructions

[ob-aion]

Summary

• Patch Vite to 8.0.16, PostCSS to 8.5.26, and Nano ID to 3.3.18; declare the Vite development peer explicitly.
• Keep project decisions in a concise AGENTS.md, imported by CLAUDE.md, and link detailed guidance to its source files. Preserve package exports, dependency limits, benchmark budgets, and release requirements.

Test plan

• Frozen lockfile installation, lint, typecheck, 97 tests with coverage, and dual package build.
• Markdownlint, instruction import and path checks, git diff --check, and redacted secret scan.