Refactor: remove desktop/Tauri bundle, add i18n, CI/CD pipeline

- Remove desktop (Tauri) bundle: docs/desktop.md, icons/, tauri.conf.json,
  src/desktop/mod.rs, gen/schemas/
- Remove build.rs (no longer needed)
- Add i18n system (crates/core-api, plugin-mobile-connector, web)
- Refactor config system (src/config.rs, boot_format.rs)
- Add mobile connector features (app, router, device pairing)
- Plugin system improvements (skald-core)
- Update dependencies (Cargo.lock, Cargo.toml)
- CI/CD: Gitea Actions workflows (nightly + release), package.sh,
  verify-version.sh, builds.skaldagent.net config

src/boot_format.rs

@@ -1,7 +1,7 @@
 //! How this binary renders the bootstrap lines that `skald_core::boot` emits.
 //!
-//! Rendering is the shell's business, not the core's: a desktop bundle or a
-//! setup wizard would format the same `boot` target differently, or not at all.
+//! Rendering is the shell's business, not the core's: another shell (e.g. the
+//! setup wizard) formats the same `boot` target differently, or not at all.
 //! Wired in `main.rs` as a stdout layer filtered on `boot::TARGET`, independent
 //! of `RUST_LOG`, so this output always appears whatever the log filter is.