fbt: initial blackmagic support (#1362)

* fbt: added separate script for Windows env setup; moved flash targets from firmware.scons to SConstruct; added Blackmagic support with automatic probe port resolution; added apps.c rebuild on any manifest.fam changes; fixed simultaneous flash & debug ops
* fbt: added networked BlackmagicResolver mode; added `get_blackmagic` target for IDE integration
* fbt: cleanup
* fbt: docs update; fixed blackmagic lookup on certain usb hubs
* fbt: removed explicit python serial port import
* fbt: cleanup
* fbt: raising exception on multiple serial blackmagic probes

fbt_options.py

@@ -41,10 +41,24 @@ COPRO_STACK_BIN_DIR = posixpath.join(
 # Supported toolchain versions
 FBT_TOOLCHAIN_VERSIONS = (" 10.3.",)
 
-OPENOCD_OPTS = '-f interface/stlink.cfg -c "transport select hla_swd" -f debug/stm32wbx.cfg -c "stm32wbx.cpu configure -rtos auto" -c "init"'
+OPENOCD_OPTS = [
+    "-f",
+    "interface/stlink.cfg",
+    "-c",
+    "transport select hla_swd",
+    "-f",
+    "debug/stm32wbx.cfg",
+    "-c",
+    "stm32wbx.cpu configure -rtos auto",
+    "-c",
+    "init",
+]
 
 SVD_FILE = "debug/STM32WB55_CM4.svd"
 
+# Look for blackmagic probe on serial ports
+BLACKMAGIC = "auto"
+
 FIRMWARE_APPS = {
     "default": [
         "crypto_start",