Add metadata to posts (conditions, country, product & category) (#36)

* Show product links in posts

* Make background darker to separate product link

* Add conditions to posts

* Add Product Posts Screen

* Show only posts for a specific product

* Increase number of lines in post text

* Add categories to posts

* Made product press dynamic

* Made product posts screen title dynamic

* Add category posts screen

* Show all products on product posts list

* Make categories appear next to product

* Add country chip

* Fix padding for product category section

* Show actual categories of products

* Make category in card clickable

* Filter by product category on category posts screen

Reorganize tabs and add "My posts" and "Profile" views (#24)

* Styled and reorganized tabs

* Change tab bar border color

* Tweak border radius and scolling

* Changed Discover icon

Add loading list of posts from Supabase (#19)