Commit Briefs
fix landlock usage
cf. gmid 1.8.1 and recent changes in game of trees. This doesn't warrant an immediate release since every action is limited to /tmp, ~/Downloads and {config,data,cache}_home.
add landlock support on linux
landlock is applied only to the ui process to drop fs access and in the fs process to limit where telescope can read/write files. The network process is more difficult to landlock because while in theory it doesn't need *any* fs access, in practice it needs to read (at least) files inside /etc/ for DNS to work.
ask to save a page when it can't be rendered
it's good for thing like images and text with weird encodings.
fix various warnings, no functional changes
now that we have a bounch of -Wxxx flags during compilation, let's fix everything.