Fix: Pin ZMK to v0.3.0 to avoid Zephyr 4.x incompatibility

The main branch of ZMK has migrated to Zephyr 4.x with Hardware Model v2 (HWMv2),
which is incompatible with the existing board definitions in boards/arm/eyelash_corne/.
Pin to v0.3.0 to match the upstream repository configuration.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

Author: user3301

config/west.yml

@@ -12,7 +12,7 @@ manifest:
       revision: main
     - name: zmk
       remote: zmkfirmware
-      revision: main
+      revision: v0.3.0
       import: app/west.yml
   self:
     path: config