Clarification on Feed Me > Feed URL
i placed  a test file named test.json in web folder of Craft CMS and put test.json in feed URL and it doesn't work -so it is not relative to web root as default-.

but when it says absolute format i believe it is  /var/www/html/craft/web/test.json -in local ubuntu, in your case maybe {maybe top folders}/public/feeds/feed.csv- or as path alias format: @webroot/test.json which both of them works for me.

as you mentioned URL format http(s)://domain.tld/test.json or @web/test.json works too.

docs for path alias