feat: DevDesk v0.1.0, a persistent browser terminal for Claude Code

ttyd serves a single-file xterm.js UI styled with the LotusGuild TDS
(web_template base.css). Sessions live in a dedicated tmux server unit
(devdesk-tmux.service), so restarting or upgrading the web unit never
stops Claude. Each named session maps to a project directory. A Claude
SessionStart hook records the conversation ID, so after a reboot the
session resumes that exact conversation.

- bin/devdesk: attach / new / ls / end / pick, with an fzf picker
- ttyd requires a credential that NPM injects; origin check enabled
- debian/: dh 13 with --no-stop-on-upgrade for the tmux unit, bundled
  sha256-verified ttyd 1.7.7, lintian overrides, man page
- CI: lint, test, build, smoke-test, artifact; v* tags publish to the
  Gitea apt registry and create a release

Refs: tinker ticket 887531976

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

libexec/devdesk-tmux-ready

@@ -0,0 +1,12 @@
+#!/bin/bash
+# ExecStartPost for devdesk-tmux.service: wait until the tmux server answers on
+# its socket, so `systemctl start devdesk-tmux` only returns once clients can attach.
+SOCK=${DEVDESK_SOCKET:-/run/devdesk/tmux.sock}
+for _ in $(seq 1 100); do
+    if [ -S "$SOCK" ] && tmux -N -S "$SOCK" start-server 2>/dev/null; then
+        exit 0
+    fi
+    sleep 0.1
+done
+echo "devdesk-tmux-ready: tmux server did not come up on $SOCK" >&2
+exit 1