docs: update to fix .polydev mentions and improper presets

docs/languages/c.md

@@ -14,7 +14,6 @@ This is the recommended file structure for your C projects using Polydev:
 | `main.c`                    | Main C file for the project                          |
 | `*.c`                       | Additional C source files                           |
 | `build/`                    | Folder where the build artifacts will be generated |
-| `<project_name>.polydev`    | Polydev metadata file (generated during build)      |
 | `include/`                  | Folder for header files                             |
 | `*.h`                       | C header files                                       |
 
@@ -29,7 +28,7 @@ Projects/
         │   ├── main.c
         │   └── *.c
         ├── build/
-        │   └── <project_name>.polydev
+        │   └── <main-executable>
         └── include/
             └── *.h
 ```

docs/languages/cpp.md

@@ -15,7 +15,6 @@ This is the recommended file structure for your C projects using Polydev:
 | `main.cpp`                  | Main Cpp file for the project                          |
 | `*.cpp`                     | Additional Cpp source files                           |
 | `build/`                    | Folder where the build artifacts will be generated |
-| `<project_name>.polydev`    | Polydev metadata file (generated during build)      |
 | `include/`                  | Folder for header files                             |
 | `*.hpp`                     | Cpp header files                                       |
 
@@ -30,7 +29,7 @@ Projects/
         │   ├── main.cpp
         │   └── *.cpp
         ├── build/
-        │   └── <project_name>.polydev
+        │   └── <main-executable>
         └── include/
             └── *.hpp
 ```

docs/languages/lua.md

@@ -14,7 +14,6 @@ Here’s the suggested directory structure for your Lua projects with Polydev:
 
 | Directory/File Path        | Description                                         |
 |----------------------------|-----------------------------------------------------|
-| `<Project_name>.polydev`    | Project metadata file that Polydev uses for configuration |
 | `lua/`                      | Directory containing the main Lua project files     |
 | `lua/<Project_name>/init.lua` | The main entry point for your Lua project          |
 
@@ -24,7 +23,6 @@ Here’s the suggested directory structure for your Lua projects with Polydev:
 Projects/
 └── Lua/
     └── Project_Name/
-        ├── <Project_name>.polydev    -- Polydev configuration file
         └── lua/
             └── Project_name/
                 └── init.lua         -- Main Lua file