1.1 Modify the virtual categories tree on the left of tt-rss under "Special".
a) Remove the "Report" category.
b) Create two new categories: Weekly and Monthly .
1.2 Modify the Entries pane to allow sending of item to the categories described above in 1.1.
a) Replace the RSS logo button on each entry, (to the left of the headline of each item) with a list box containing: Send Now, Weekly, Monthly (default text, before selection is "Report")
b) Upon selection of "Send Now" the functionality that runs the mail plugin executes. dev note: To find that UI in existing, try pressing the little email icon in lower-right of each entry.
c) Upon selection of Weekly or Monthly, the user_entry is marked in user_entries table using a new column that you create.
d) The category tree on the left is refreshed to show this item in the correct report.
The "category tree" refers to the left "menu bar."
"Entries" are individual RSS entries which are displayed in the main content of the page.
Basically what you are doing here is cloning the current functionality of the way the RSS icon shows items under the "Report" button on each entry, but making 2 of them.
See https://github.com/gothfox/Tiny-Tiny-RSS for a reference of the base code.