vcreate: update templates, add lib (#19444)

cmd/tools/vcreate/project_model_bin.v

@@ -0,0 +1,13 @@
+module main
+
+fn (mut c Create) set_bin_project_files(new bool) {
+	c.files << ProjectFiles{
+		path: if new { '${c.name}/src/main.v' } else { 'src/main.v' }
+		content: "module main
+
+fn main() {
+	println('Hello World!')
+}
+"
+	}
+}

cmd/tools/vcreate/project_model_lib.v

@@ -0,0 +1,23 @@
+module main
+
+fn (mut c Create) set_lib_project_files() {
+	c.files << ProjectFiles{
+		path: '${c.name}/src/${c.name}.v'
+		content: 'module ${c.name}
+
+// square calculates the second power of `x`
+pub fn square(x int) int {
+	return x * x
+}
+'
+	}
+	c.files << ProjectFiles{
+		path: '${c.name}/tests/square_test.v'
+		content: 'import ${c.name}
+
+fn test_square() {
+	assert ${c.name}.square(2) == 4
+}
+'
+	}
+}