v1.0.0: merge container (scrollbox + tabbar) into cl-tty.box

Eliminates the cl-tty.container package by merging scrollbox and tabbar
components directly into cl-tty.box, where the component system lives.

Changes:
- added scrollbox/tabbar exports to cl-tty.box defpackage in package.org
- changed scrollbox.org in-package from cl-tty.container to cl-tty.box
- changed tabbar.org in-package from cl-tty.container to cl-tty.box
- tabbar's key-event-key references are qualified with cl-tty.input:
  (avoids circular :use dependency with cl-tty.input which :uses cl-tty.box)
- deleted container-package.org
- updated test packages, integration tests, scripts, ASDF
- all 14 test suites pass at 100%

org/tabbar.org

@@ -33,7 +33,7 @@ the symbol namespace clean and avoids accidental collisions with
 user-level code.
 
 #+BEGIN_SRC lisp :tangle ~/.local/share/cl-tty/src/components/tabbar.lisp
-(in-package #:cl-tty.container)
+(in-package :cl-tty.box)
 #+END_SRC
 
 ** TabBar class
@@ -168,7 +168,7 @@ bar lives alongside other focusable elements.
 #+BEGIN_SRC lisp :tangle ~/.local/share/cl-tty/src/components/tabbar.lisp
 (defun tab-bar-handle-key (tb event)
   "Handle a key-event on a TabBar. Returns T if handled."
-  (case (key-event-key event)
+  (case (cl-tty.input:key-event-key event)
     (:left (tab-bar-prev tb) t)
     (:right (tab-bar-next tb) t)
     (t nil)))