Change io crate & add a small shell

Cargo.toml

@@ -1,7 +1,7 @@
 [workspace]
 resolver = "3"
-members = ["user/*"]
-exclude = ["library", "build-tools"]
+members = ["crates/ansii","user/*"]
+exclude = ["library", "build-tools", "crates/io"]
 
 [package]
 name = "kernel-rust"
@@ -13,10 +13,11 @@ bitflags = "2"
 embedded-alloc = "0.7"
 kernel-macros = { path = "crates/kernel-macros" }
 bytes-struct = { path = "crates/bytes-struct" }
+ansii = { path = "crates/ansii" }
 log = "0.4"
 critical-section = { version = "1", features = ["restore-state-bool"] }
 bffs = { path = "crates/bffs", features = ["alloc"] }
-io = { path = "crates/io", features = ["alloc"] }
+io = { package = "no-std-io", path = "crates/io" }
 shared = { path = "crates/shared", features = ["kernel"] }
 goblin = { version = "0.7", default-features = false, features = ["elf32", "elf64", "endian_fd"] }
 hashbrown = "0.16"