Refine style of <rpg-character>

Issues with the current style:

[x] The way the cards wrap on the screen is disorienting. Change it to a list.
[x] Jim's character portraits are too large (~3MB, see #24), so upload some resized ones to Firebase for now
[x] Dummy text should be replaced with actual values from the spreadsheet (race, job)
[x] The View Character Sheet button causes other cards to be misaligned (changing to a list will help with this)
[x] The images aren't cached properly (this may not matter if we're serving small images)
[ ] "Your character(s)" should float to the top as a subheader
[ ] "Other player characters" subheader should list other players in alphabetical order
[ ] "Non-player characters" subheader beneath that
[ ] Nice to have: when a character is selected, use hero-animation to transition to the detail view

toxoplasmotic / ripage-web