Add .gitignore file and refactor llcc68 component

- Added a comprehensive .gitignore file to exclude unnecessary files and directories for various platforms and tools.
- Removed the llcc68.cpp source file as part of the refactoring process.
- Updated llcc68.hpp to replace the `init_exti` function declaration with inline interrupt configuration logic.
- Changed `EXTI_PIN` to `EXTI_PINS` for clarity and consistency.
- Refactored the handling of CAD parameters and improved type safety by using `enum class` for `CAD_EXIT_MODE` and `CAD_SYMB`.

inc/template/app_const_llcc68_template.hpp

@@ -28,7 +28,7 @@ constexpr auto DIO2_PIN = NC_PIN;
 constexpr auto DIO3_PIN = NC_PIN;
 
 /// @brief the pin numbers that needs to be configured as interrupt
-constexpr gpio_num_t EXTI_PIN[] = {DIO1_PIN};
+constexpr gpio_num_t EXTI_PINS[] = {DIO1_PIN};
 }
 
 #endif /* B0CD865F_D860_44B7_B289_4F512C770D2B */