Rename file while in the Share/Upload intent

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**Is your feature request related to a problem? Please describe.**
"I'm always frustraded when" I have to first upload a file to my Nextcloud and then rename it to the proper file name convention i use. For example, I receive mails from utility companies with home bills, each in its own filename format, but I want to store them using my own date-based convention, e.g. `202602-Electricity.pdf` vs `202603-Internet.pdf` for sake of my neurons. In general, I tend to timestamp almost all my files in my Nextcloud.

Today, I need to do it in two steps: one is upload of file, and then I have to go seek the file and rename it.

**Describe the solution you'd like**
I would like to change the dialog screen that responds to the "Share" intent for files, adding an editable text box field with the file's original name (e.g. `Your_Monthly_Power_Bill_By_ShinraCorporation_Feb26.pdf`) as provided in the Android's intent, so that if the user changes the text box content the file will be uploaded to Nextcloud using the user-supplied name.

**Describe alternatives you've considered**
None

**Additional context**
In general, I have coding expertise in Java and some old experience in Android development (also all the tools need to develop), but not sure how long it will take to me to become more familiar with Nexcloud app codebase.
Let's first see if the feature is desirable