refactors + adds sidebar to account settings

[mekarpeles]

Refactors the sidebar out of the account/books.html template and plugins/mybooks.py so that it can be added/used w/ the /account settings page.

Technical

NB: The old sidebar.html code is remains / is duplicated by this PR and needs to be consolidated + cleaned up in account/books.html template

Testing

Screenshot

Stakeholders

@jimchamp @cdrini

[mekarpeles]

After this refactor PR lands, @tangym27 can follow the example of the Settings Page changes in this PR to also add this new sidebar to the patron Profile Page whose code lives in https://github.com/internetarchive/openlibrary/blob/master/openlibrary/templates/type/user/view.html

[jimchamp]

I'm reviewing this now. Why was it converted to a draft?

[mekarpeles]

It was originally converted to draft because the code in books.html remained duplicated and has since been migrated into sidebar.html

[mekarpeles]

Just worked through a final bug w/ @jimchamp re: selected List pages (by pulling the selected list key from the ctx.path current url)

[jimchamp]

Lgtm! Tested that sidebar bug has been resolved on testing.

[jimchamp]

The sidebar is not rendering because it is missing items, which is only used here to determine if the current list is selected:

In the list context, items is the list itself, which is probably overkill to send to the sidebar template. Maybe sending the list ID as the key would work better:

Suggested change

	$if lst == items:
	$if list_id == key:

[jimchamp]

As an aside, it was wrong of me to name that parameter key, as it doesn't fit the pattern of OL keys. Maybe selection is better? Anyway, this doesn't need to be changed now.

[jimchamp]

Anyway, you'll have to set the key for lists here:

openlibrary/openlibrary/plugins/upstream/mybooks.py

Lines 219 to 220 in 75b3ab6

	elif self.key == 'list':
	data = list

Adding the following at the end of that block worked for me:
self.key = list.key.split('/')[-1]