Initial commit — Stage 0 project foundation

- Cargo workspace with engine, editor, tests crates
- oxide-editor binary stub (builds and runs cleanly)
- install.sh for Linux system installation
- README.md with logo, build and install instructions
- GPLv3 LICENSE
- .gitignore

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

editor/Cargo.toml

@@ -0,0 +1,18 @@
+[package]
+name = "oxide-editor"
+description = "Oxide Engine — in-engine editor"
+version.workspace = true
+edition.workspace = true
+authors.workspace = true
+license.workspace = true
+rust-version.workspace = true
+
+[[bin]]
+name = "oxide-editor"
+path = "src/main.rs"
+
+[dependencies]
+oxide-engine = { path = "../engine" }
+log.workspace = true
+env_logger.workspace = true
+anyhow.workspace = true

editor/src/main.rs

@@ -0,0 +1,14 @@
+//! Oxide Editor — entry point.
+//!
+//! The in-engine editor is built as a first-class part of the Oxide project.
+//! It grows alongside the engine, gaining new panels and tools at each stage.
+
+#![deny(warnings)]
+
+fn main() {
+    env_logger::init();
+    log::info!("Oxide Editor starting…");
+
+    // Editor shell will be populated as engine systems come online.
+    println!("Oxide Editor — not yet implemented. Build the engine first.");
+}