Harden repository for agent-guided contribution workflow

[senolcolak]

Context

The repository structure and AGENTS.md are now in place. The next step is to make RustShare consistently usable by human contributors and AI coding agents such as Codex, Claude Code, or similar tools.

RustShare is expected to become durable company memory infrastructure, so the repo needs clear contribution rules around storage, permissions, indexing, connectors, and future RAG-related work. The goal is to keep the workflow practical and lean while borrowing the useful parts of mature Rust repositories such as Turso.

Scope

• Review AGENTS.md against the current repository layout and make sure all paths, crate names, and commands are accurate.
• Ensure README.md and CONTRIBUTING.md point contributors to AGENTS.md where appropriate.
• Add or update lightweight agent/contributor docs, for example:
  • docs/agent-guides/testing.md
  • docs/agent-guides/code-quality.md
  • docs/agent-guides/pr-workflow.md
  • docs/architecture/overview.md
  • docs/security/permissions.md, if not already covered elsewhere
• Document the expected local validation commands:
  • cargo fmt --check
  • cargo clippy --workspace --all-features --all-targets -- --deny warnings
  • cargo test --workspace
• Review CI and make sure the same basic quality gates are enforced.
• Add or update PR / issue templates if missing.

RustShare-specific notes

Please make the contribution guidance explicit about the main RustShare boundaries:

• durable artifact/file model
• folders and metadata
• permissions and access control
• indexing and future RAG behavior
• Obsidian / Markdown / external connector behavior
• migrations and data compatibility

Permission-related changes should require extra care. Any change touching access control, indexing visibility, or future RAG context boundaries should include tests and a short security note in the PR.

Acceptance criteria

• AGENTS.md accurately reflects the current RustShare repo layout.
• The main build, lint, format, and test commands are documented and work locally.
• CI enforces the same baseline quality gates.
• README.md / CONTRIBUTING.md link to the agent/contributor workflow.
• At least one short agent guide exists for testing and PR workflow.
• Permission-sensitive areas are clearly marked for human review.
• The repo makes it clear what an AI agent may change and what requires human review.
• The guidance stays lean and does not introduce unnecessary process overhead.