Make the chunk-based upload work more consistently

Fix/remove the denosass dependency (#177)

Fixes #177

Update Deno and remove `--unstable-no-legacy-abort` "hacks"

Addresses the UX/UI bug at #175 (comment)

Fix changing email

Fixes #175

Update Deno and dependencies, prepare for new release

Update default version for release

Fix potential XSS in RSS feed reader

Update default docker image version

Fix lint and update deno

Fix (potential) security vulnerability

Basically an attacker could try to get a file from the server if knowing/guessing the name, via the public/ file handler. Big facepalm no one'd noticed so far (this is safeguarded in the files model for user files, but not through the public route handler).

Note that I tried but wasn't able to actually exploit this (I'm honestly unsure why, but wanted to get this out ASAP).