refactor(firmware): centralize configuration and diagnostics

firmware/libs/kaptan-config-derive/tests/ui/mixed_section_scalar.stderr

@@ -1,5 +1,5 @@
-error: ConfigValidate records must contain either scalar config fields or config(section) fields exclusively
- --> tests/ui/mixed_section_scalar.rs:6:5
+error: Config records must contain either scalar fields or child configuration records exclusively
+ --> tests/ui/mixed_section_scalar.rs:5:5
   |
-6 |     child: u32,
+5 |     child: u32,
   |     ^^^^^