Placeholders fileFormat and fileFormatUppercase for folder naming of Quick Conversion

[porg]

[Added] QuickConvert dropdown menu gets options to include batch-name and quality-parameter into file/folder name implemented a custom name with static text plus placeholders (= variables) for the subfolder name used for converted files or the subfolder name for moved original files.

This is a request to introduce these missing placeholders:
• &fileFormatExt;
• &fileFormatExtUppercase;

Remarks:
• This simply is the corresponding file extension of the chosen file format of the quick conversion in lower case (by default) or upper case.
• If the parser supports case sensitive differentiation then I'd prefer &ext; and &EXT; for brevity.

For example folder name "&fileFormatExtUppercase; &batchname; q&quality;" would yield instances like:
• JPG 50pc q60
• WEBP 1280max q80

[porg]

@forum_adm : A response would be appreciated.

[forum_adm]

I added it to build 5678.

[porg]

Tested in build 5681. Worked perfectly:
in the preview of the destination folder name in context menu
and in the created folder name when executed

To complete this feature, please improve the help text from:

&fileFormatExt; - lowercase file format extensions
&fileFormatExtUppercase; - uppercase file format extensions

To new text:

&fileFormatExt; — File extension of the chosen output format in lowercase.
&fileFormatExtUppercase; — File extension of the chosen output format in uppercase.

Rationale:
- "extensions" (plural) is wrong b/c in one conversion there's always only one output format, hence definitive article "the" to be absolutely clear on this.
- Please change all separators in the help text from "-" (minus) to a long dash "—" or double minus "--" to be clearly recognizable as a separator.