Scaffold cli-rust: Rust CLI client for traverse-starter

[enricopiovesan]

Summary

Create apps/traverse-starter/cli-rust/ — a Rust CLI client that invokes traverse-starter.process from the terminal. Phase 1 uses HTTP polling matching web-react. Shares traverse-core-rs crate with the Linux GTK client (see #59). SSE is the phase 2 upgrade path.

Phase 1 scope (HTTP polling — unblocked)

• CLI tool: traverse-starter run --note "..." → POST execute → poll → print result
• Runtime URL + workspace via CLI flags or env vars (TRAVERSE_BASE_URL, TRAVERSE_WORKSPACE)
• Health check subcommand: traverse-starter health
• Structured output: human-readable by default, --json flag for machine output
• Demonstrates Traverse as a programmable backend — agent/CI-friendly

Stack

Concern	Choice
Language	Rust
CLI	clap (derive API)
HTTP	reqwest (blocking or async with Tokio)
Output	colored for human, serde_json for --json

Directory structure

apps/traverse-starter/cli-rust/
  Cargo.toml
  src/
    main.rs                       # clap entrypoint
    commands/
      run.rs                      # execute + poll loop
      health.rs
    client.rs                     # reqwest HTTP client
    output.rs                     # human + JSON formatters
  tests/
    integration_tests.rs

Commands

traverse-starter run --note "Meeting with Alice about project X"
traverse-starter run --note "..." --json
traverse-starter health
traverse-starter run --base-url http://192.168.1.42:8787 --workspace my-workspace --note "..."

Phase 2 upgrade path (do not implement now)

When Traverse ships #525 / #526 / #527:

• Replace polling with SSE streaming — print state transitions to stdout as they arrive
• Move HTTP + SSE client into shared traverse-core-rs crate (see Extract traverse-core-rs: shared Rust HTTP/SSE crate for linux-gtk and cli-rust #59)
• Add send-command subcommand for manual command dispatch

Definition of Done

• cargo build succeeds on macOS and Linux
• traverse-starter run --note "..." executes, polls, and prints result
• --json flag outputs machine-readable JSON
• traverse-starter health prints runtime status
• --base-url and --workspace flags + env var fallbacks work
• Integration test against a live runtime (or mock server)
• README in cli-rust/ covering: build, install, usage examples
• scripts/ci/repository_checks.sh updated to acknowledge cli-rust/ directory

[enricopiovesan]

Design language reference: docs/design-language.md (added in #74 / #60). Platform client DOD should follow the three-zone IA and field naming there.