feat(rules): list and install rustinel-rules packs

[Karib0u]

Purpose

Allow Rustinel to discover and install one active cumulative rules profile from the released rustinel-rules catalog without requiring users to manually edit config.toml.

Scope

• Add rustinel rules list.
• Add rustinel rules install <PACK>.
• Fetch and parse the released index.json catalog.
• Filter packs for the current platform.
• Validate manifest schema and engine paths.
• Validate pack operating system.
• Validate requires_rustinel compatibility.
• Define and implement the Phase 1 catalog trust model.
• Download artifacts into staging.
• Enforce maximum download and extracted sizes.
• Verify SHA-256 checksums.
• Reject ZIP path traversal and unsafe entries.
• Validate expected pack structure.
• Atomically replace rules/current.
• Write state.json with pack ID, version, checksum, and installation timestamp.
• Preserve the previous working pack on failure.

Managed Rules Layout

rules/
├── current/
│   ├── pack.yml
│   ├── sigma/
│   ├── yara/
│   └── ioc/
├── staging/
└── state.json

Acceptance Criteria

• rules list shows available packs for the current platform.
• The active pack is clearly identified.
• rules install validates OS and minimum Rustinel version.
• Catalog trust is verified or the release limitation is explicitly documented before release.
• SHA-256 verification is mandatory.
• Unsafe ZIP entries are rejected.
• Failed installation preserves the active working pack.
• Tests use local fixtures rather than depending on live GitHub releases.

Dependencies

• feat(config): add portable and managed installation layouts #103

Priority

P0