Remove Cargo.toml files from el-ui — vessels use manifest.el

All package management is through manifest.el / epm. Cargo.toml files
were incorrectly added to vessels and the root. Removed root workspace
Cargo.toml + Cargo.lock and all vessel-level Cargo.toml files.

el-graph and el-html were already correct (no Cargo.toml).

ui/vessels/el-publish/Cargo.toml

@@ -1,15 +0,0 @@
-[package]
-name = "el-publish"
-version = "0.1.0"
-edition = "2021"
-description = "el-ui app publishing pipeline — one command ships to every platform"
-license = "MIT"
-
-[lib]
-name = "el_publish"
-path = "src/lib.rs"
-
-[dependencies]
-thiserror = "1"
-
-[dev-dependencies]