feat(ci): dynamic solo firmware build workflow, add _solo_dual envs for Wio Tracker L1

- Add build-solo-firmwares.yml: auto-detects all _solo_dual envs from platformio.ini, builds in parallel, publishes uf2 files to draft release
- Remove build-wio-tracker-l1-firmwares.yml (replaced by solo workflow)
- Add WioTrackerL1_companion_solo_dual and WioTrackerL1Eink_companion_solo_dual envs
- Wire build-solo-firmwares command in build.sh using _solo_dual suffix

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

variants/wio-tracker-l1-eink/platformio.ini

@@ -69,6 +69,13 @@ build_flags = ${WioTrackerL1Eink.build_flags}
   -D DUAL_SERIAL=1
 extra_scripts = post:create-uf2.py
 
+; Dual BLE+USB with added Solo
+[env:WioTrackerL1Eink_companion_solo_dual]
+extends = WioTrackerL1Eink
+build_flags = ${WioTrackerL1Eink.build_flags}
+  -D DUAL_SERIAL=1
+extra_scripts = post:create-uf2.py
+
 ; Dual BLE+USB with screenshot support (development/debug)
 [env:WioTrackerL1Eink_companion_dual_dev]
 extends = WioTrackerL1Eink

variants/wio-tracker-l1/platformio.ini

@@ -144,15 +144,18 @@ build_flags = ${WioTrackerL1CompanionBLE.build_flags}
   -D DUAL_SERIAL=1
   -UBLE_DEBUG_LOGGING
 
-[env:WioTrackerL1_companion_radio_dual]
-extends = WioTrackerL1CompanionDual
-
 [env:WioTrackerL1_companion_dual]
 extends = WioTrackerL1CompanionDual
 build_flags = ${WioTrackerL1CompanionDual.build_flags}
   -D UI_HAS_JOYSTICK_UPDOWN=1
 extra_scripts = post:create-uf2.py
 
+[env:WioTrackerL1_companion_solo_dual]
+extends = WioTrackerL1CompanionDual
+build_flags = ${WioTrackerL1CompanionDual.build_flags}
+  -D UI_HAS_JOYSTICK_UPDOWN=1
+extra_scripts = post:create-uf2.py
+
 [env:WioTrackerL1_companion_dual_dev]
 extends = WioTrackerL1CompanionDual
 build_flags = ${WioTrackerL1CompanionDual.build_flags}