[chore][build]: Update platformio.ini: restructure environments and platform_packages.

- Split platform_packages configuration for default, staging, test and dev environments.
- Assign specific framework-arduinopico sources and versions per environment.
- Remove redundant, now default `-DLIB_PICO_MULTICORE=1` build flag.
- Improve clarity and maintainability of environment-specific settings.

Signed-off-by: Goran Mišković <[email protected]>

Author: schkovich

platformio.ini

@@ -3,30 +3,32 @@ board = nanorp2040connect
 framework = arduino
 platform = https://github.com/maxgerhardt/platform-raspberrypi.git
 board_build.core = earlephilhower
-platform_packages =
-    framework-arduinopico@symlink://../arduino-pico
 upload_protocol = cmsis-dap
-monitor_port = /dev/ttyACM1
 monitor_speed = 115200
-
-[env:test]
 build_flags =
     -DESPHOSTSPI=SPI
-    -DLIB_PICO_MULTICORE=1
+
+[env:default]
+platform_packages =
+    framework-arduinopico@https://github.com/earlephilhower/arduino-pico.git#4.7.0
+
+[env:staging]
+platform_packages =
+    framework-arduinopico@https://github.com/schkovich/arduino-pico.git#4.7.0
+
+[env:test]
+platform_packages =
+    framework-arduinopico@symlink://../arduino-pico
 debug_tool = cmsis-dap
 debug_extra_cmds =
     set remotetimeout 5
     source scripts/combined_debug.gdb
 
-[env:staging]
-build_flags =
-    -DESPHOSTSPI=SPI
-    -DLIB_PICO_MULTICORE=1
-
 [env:dev]
+platform_packages =
+    framework-arduinopico@symlink://../arduino-pico
 build_flags =
     -DESPHOSTSPI=SPI
-    -DLIB_PICO_MULTICORE=1
     -DDEBUG_RP2040_PORT=Serial1
     -DDEBUG_RP2040_CORE
     -DDEBUG_RP2040_WIRE