dot-request: --inbox, and xz compression past 400 KB

--inbox files into another inbox than dot: the path it posts to and the
namespace it signs in both follow it, so the key signs for that inbox only.
DOT_REQUEST_URL still overrides the whole URL for testing.

A signed request over 400 KB -- the inbox's limit on the wire -- now goes
xz -9e compressed with Content-Encoding: xz, which the inbox undoes before
checking anything; a smaller one goes as it is. --compress and --no-compress
override that either way. Compressing needs xz, so it joins the Brewfile;
without it a request that must be compressed is refused, never sent plain.

Checked against a local inbox: 148 KB sent plain, 740 KB compressed to 37 KB
and accepted, --no-compress over the limit refused with 413, --compress on a
small request accepted, a bad --inbox name refused before signing.

1 files changed, 1 insertions, 0 deletions

diff --git a/Brewfile b/Brewfile
index 6f3f465..bbf4f2a 100644
--- a/Brewfile
+++ b/Brewfile
@@ -26,6 +26,7 @@ brew "gh"                  # config/profile hands it the GitHub token
 brew "mosh"                # alacritty-mosh, mosh-tmux.sh
 brew "terminal-notifier"   # bin/notify
 brew "fswatch"             # bin/sz-wait-for
+brew "xz"                  # bin/dot-request, for requests over 400 KB
 brew "n"                   # node versions, under $N_PREFIX
 brew "bash-completion"
 brew "shellcheck"