wasm: support more vendor libraries

Adds support for:
- box2d
- cgltf
- stb image
- stb rect pack

vendor/libc/assert.odin

@@ -0,0 +1,15 @@
+package odin_libc
+
+import "base:runtime"
+
+@(require, linkage="strong", link_name="__odin_libc_assert_fail")
+__odin_libc_assert_fail :: proc "c" (func: cstring, file: cstring, line: i32, expr: cstring) -> ! {
+	context = g_ctx
+	loc := runtime.Source_Code_Location{
+		file_path = string(file),
+		line      = line,
+		column    = 0,
+		procedure = string(func),
+	}
+	context.assertion_failure_proc("runtime assertion", string(expr), loc)
+}