Release NIT System 0.4.0

[ART3121]

What changed

• restructures NIT System as coordinated Core, CLI, TUI, NIT Cat, AI, and Editor crates
• adds the standalone nitcat Markdown viewer, shell completion, per-Note Markdown storage, and expanded TUI management
• hardens parsing, concurrent persistence, transaction recovery, terminal cleanup, local Ollama access, and installer validation
• updates the public README, component documentation, architecture/philosophy guides, migration instructions, and changelog

Why

Version 0.4 moves NIT from rapid capture toward a complete modular terminal note manager while preserving local-first, human-readable storage and Unix-oriented composition.

Compatibility

• source builds require Rust 1.88+
• release archives currently target Linux x86-64
• version 0.2 workspaces are migrated through validated, backup-preserving paths
• nit -ls replaces nit -list; Note viewing moves from nit -v to nitcat <NOTE-ID>

Validation

• cargo fmt --all --check
• cargo clippy --workspace --all-targets --all-features --locked -- -D warnings
• cargo test --workspace --locked (107 tests)
• cargo build --workspace --release --locked
• cargo doc --workspace --no-deps --locked
• cargo audit (0 known vulnerabilities)
• sh -n install.sh
• git diff --check