refactor: 拆分 oxide_ir 为独立 crate

crates/oxide_compiler/Cargo.toml

@@ -10,10 +10,10 @@ description = "OxideJS - AST to bytecode compiler"
 oxide_bytecode = { path = "../oxide_bytecode" }
 oxide_parser = { path = "../oxide_parser" }
 oxide_log = { path = "../oxide_log" }
+oxide_ir.workspace = true
 serde.workspace = true
 serde_json.workspace = true
 rustc-hash.workspace = true
-smallvec.workspace = true
 
 [dev-dependencies]
 oxide_code_cache = { path = "../oxide_code_cache" }