Add initial project structure and implement async main for Pico W

Cargo.lock

@@ -181,6 +181,15 @@ dependencies = [
  "syn 2.0.117",
 ]
 
+[[package]]
+name = "cortex-m-semihosting"
+version = "0.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c23234600452033cc77e4b761e740e02d2c4168e11dbf36ab14a0f58973592b0"
+dependencies = [
+ "cortex-m",
+]
+
 [[package]]
 name = "crc-any"
 version = "2.5.0"
@@ -329,6 +338,29 @@ dependencies = [
  "defmt 0.3.100",
 ]
 
+[[package]]
+name = "defmt-test"
+version = "0.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1c1e67ff0e1c6b1a9540a1a3e04454658faacdd188c91987c444d56e469d7dea"
+dependencies = [
+ "cortex-m-rt",
+ "cortex-m-semihosting",
+ "defmt 0.3.100",
+ "defmt-test-macros",
+]
+
+[[package]]
+name = "defmt-test-macros"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fe5520fd36862f281c026abeaab153ebbc001717c29a9b8e5ba9704d8f3a879d"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.117",
+]
+
 [[package]]
 name = "diff"
 version = "0.1.13"
@@ -1368,6 +1400,7 @@ dependencies = [
  "cyw43-pio",
  "defmt 0.3.100",
  "defmt-rtt",
+ "defmt-test",
  "embassy-executor",
  "embassy-net",
  "embassy-rp",