add new and init to toolchain

README.md

@@ -31,9 +31,12 @@ invocation in command-line order:
 C preprocessing.
 
 Instead of passing these on the command line, a project can describe its build
-in Brolang itself. `brolang build [root]` (root defaults to the current
-directory) reads a `config` constant from `root/build.bro` and compiles the
-program package it names:
+in Brolang itself. `brolang new <project>` creates a project with local `std`
+and `ffi` copies; `brolang init` does the same for the current directory without
+overwriting existing files. `brolang build [root]` reads a `config` constant
+from `root/build.bro` and compiles the program package it names. Without
+`root`, it searches the current directory and parents for the nearest
+`build.bro`. Build outputs are written to `root/build/<name>`.
 
 ```bro
 b :: import "@std/build"
@@ -49,12 +52,12 @@ config :: b.BuildConfig{
 }
 ```
 
-`source` is the program package, relative to `build.bro`. The list fields map to
-the matching C options (`libraries` → `-l`, `lib_paths` → `-L`, `includes` →
-`-I`, `defines` → C defines, `links` → linker inputs) and, like those flags,
-their paths are relative to the invocation directory. Lists take the address of
-an array literal; empty lists are written `&[]`. See `examples/build/` for
-runnable projects.
+`name` is a plain executable name, and `source` is the program package relative
+to `build.bro`. The list fields map to the matching C options (`libraries` →
+`-l`, `lib_paths` → `-L`, `includes` → `-I`, `defines` → C defines, `links` →
+linker inputs) and, like those flags, their paths are relative to the invocation
+directory. Lists take the address of an array literal; empty lists are written
+`&[]`. See `examples/build/` for runnable projects.
 
 Relative `.h` imports create synthetic package namespaces backed by libclang:
 
@@ -146,11 +149,12 @@ specialization is demanded.
 
 Every immediate `.bro` file in the input directory belongs to the root
 package. Imports are relative directory paths and are local to the file that
-declares them:
+declares them. Imports beginning with `@` resolve from the project root:
 
 ```bro
 import "../math"
 other_math :: import "../math"
+heap :: import "@std/mem/heap"
 
 value :: math.sum(other_math.value, 1)
 ```