Fix crash on UNDO/REDO shortcut press when in "title screen"
### Problem description
ImHex crashes when (by default CTRL + Z/Y) undo/redo is pressed when on
"title"/"starting" screen (no file open, tested on Windows release build
and Linux [WSL] from-source build).
This is due to the shortcut's callback being called even if the
`provider` is `nullptr`. (see `createEditMenu` function).
Theoretically, this is prevented by the `enabledCallback` function
passsed to `addMenuItem`. In this case, though,
`addMenuItem` correctly propagates `enabledCallback` to menu item
creation but does not pass `enabledCallback` to
shortcut creation. Thus, when handling shortcuts, `enabledCallback` is
not used at all and the shortcut's callback
can be called in contradiction with its preconditions. (specified by
`enabledCallback`)
### Implementation description
The implementation wraps the callback in a check that decides whether
the shortcut is enabled or not.
(see changed files)
```c++
auto callbackIfEnabled = [enabledCallback, function]{ if (enabledCallback()) { function(); } };
```
This function is then passed along instead of the `function` (shortcut's
callback).
Alternatively, we can check for `nullptr` in the callback directly. This
would require modification of `createEditMenu`'s contents.
(I did not choose this implementation because I do not think it
addresses the root of the issue).
### Screenshots
None
### Additional things
I'm not sure how big of a deal it is but I am unsure whether I can
capture (`[enabledCallback, function]`) by reference or not.
### Problem description
Loading a file on the command line or using the context menu in windows
was triggering an achievement before the achievements file was loaded.
This resulted on the achievements.json file to be overwritten with all
the achievements reset except for the one to open files.
### Implementation description
This PR fixes the problem by introducing a boolean that is used to check
if the file has been loaded.
---------
Co-authored-by: Nik <werwolv98@gmail.com>
### Problem description
The default result export functionality of the Find tool is limited to
only exporting data in a nonstandard text format. This PR adds support
for exporting the results in CSV, TSV or JSON format. The PR also
removes the old format.
### Implementation description
I added the classes `ExportFormatter`, `ExportFormatterCsv`,
`ExportFormatterTsv` and `ExportFormatterJson`, with similar
implementations to the pattern data exporters.
~~I also moved the `ViewFind::Occurrence` class into
`hex/helpers/types.hh`, so the exporters can access it.~~
### Screenshots
### Additional things
Another small change I made is moving the "{} entries found" line on the
same line as the Search and Reset buttons. I think it looks cleaner this
way, but if anyone disagrees, I can revert it.
---------
Co-authored-by: WerWolv <werwolv98@gmail.com>
