Add new app "hopper" app.

[zxkmm]

There are one thing to discuss:
jammer app is a bit weird designed, that they claimed a ram region like this:

struct SharedMemory {
// ...

    union {
        ToneData tones_data;
        JammerChannel jammer_channels[24];
        uint8_t data[512];
    } bb_data{{{{0, 0}}, 0, {0}}};

// ...
}

Which sort of looks like a thing that communication between m0 and m4. I don't know how it use the ram but it looks like it will always in ram. and if we wanna keep both app, the only way would be i claim another region something like this:

   union {
        ToneData tones_data;
        JammerChannel jammer_channels[24];
        HopperChannel hopper_channels[xxxxxxx];
        uint8_t data[xxxxxxx];
    } bb_data{{{{0, 0}}, 0, {0}}};

AI summary

This pull request introduces a new external application called "Hopper" to the firmware. The changes include updates to multiple files to integrate this new application, including adding the necessary source files, memory allocation, and UI components.

Integration of Hopper application:

• firmware/application/external/external.cmake: Added hopper source files to EXTCPPSRC and hopper to EXTAPPLIST. [1] [2]
• firmware/application/external/external.ld: Allocated memory for the hopper application and added sections for it. [1] [2]

New source files for Hopper:

• firmware/application/external/hopper/main.cpp: Added the main implementation file for the hopper application, including initialization and application information.
• firmware/application/external/hopper/ui_hopper.cpp: Added the UI implementation for the hopper application, including frequency management and transmission control.
• firmware/application/external/hopper/ui_hopper.hpp: Added the header file for the hopper UI, defining the HopperView class and its methods.

File path updates:

• firmware/application/file_path.cpp: Added hopper_dir path for storing Hopper-related files.
• firmware/application/file_path.hpp: Declared the hopper_dir path.

Shared memory and navigation updates:

• firmware/common/portapack_shared_memory.hpp: Added HopperChannel struct and updated shared memory to include hopper_channels. [1] [2]
• firmware/application/ui_navigation.cpp: Commented out the subghzd entry in the app list.

[gullradriel]

Hey @zxkmm , still a draft ?
:-)

[zxkmm]

Ya sorry gull, the new path declaration extends the inner space and I need to move an app to external before this merged XD

[gullradriel]

Yeah, we're short on firmware space.
I may make a externalize PR this afternoon.

[gullradriel]

I fixed the conflicts.

[zxkmm]

Thank you!