v0.16.0

• Redesign the SDK to a builders-only API across all four languages, removing legacy build_json_ok/build_json_error constructors and collapsing every _with_options variant into a single function with optional parameters
• Introduce AFDATA protocol v1: a finite CLI event stream of (log|progress)* followed by exactly one result or error, with typed envelopes carrying code, message, and an optional trace
• Add semantic CLI emitter methods (emit_result/emit_error/emit_progress/emit_log) that validate envelope shape and enforce the single-terminal-event lifecycle at the emitter
• Support protocol-compliant early exits so --help and --version emit structured events when --output json|yaml|plain is requested
• Route structured logging through protocol v1 log events, including a redacted startup diagnostic capturing resolved config, argv, and environment
• Add a machine-readable suffix registry and protocol JSON Schema, bundled as offline reference assets in every language package
• Add the _{code}_micro currency suffix for sub-cent precision as integer millionths of a currency unit, aimed at per-token LLM and metered-API pricing
• Publish a standard Agent Skill plus a skill-admin CLI subcommand that installs and serves the skill offline
• Harden redaction to scrub raw argv secrets, _url userinfo passwords and secret-named query parameters, and secret-flag help defaults
• Add optional stdout/stderr file redirection so services separate machine-readable protocol events from diagnostic output
• Distribute the afdata CLI as prebuilt binaries via Homebrew and Scoop in addition to crates.io, npm, and PyPI