nexo-plugin-manifest 0.1.8

TOML manifest schema + 4-tier validator for native Rust nexo plugins (Phase 81.1).
Documentation

nexo-plugin.toml manifest schema + validator.

Defines the TOML manifest contract every native Rust nexo plugin must ship.

Distinction vs crates/extensions/<n>/plugin.toml: that schema describes subprocess tool extensions (stdio / HTTP MCP servers spawned as separate processes). This schema describes native Rust plugins that link into the daemon and ship full mini-applications (agents + tools + skills + channels + advisors + capability gates).