v0.7.0: char-width + status bar fix — TDD (RED→GREEN)

char-width: contract 5, 4 tests (6 assertions), 100% pass
  ASCII=1, CJK/Hangul/Kana/halfwidth=2, combining marks=0, tab=8
  Pure Lisp, ~25 lines, no deps. Used by word-wrap for unicode.

status bar: contract 6, timestamp right-aligned at (- w 12)
  Fixes overlap where focus map and timestamp both drew at :y 2 :x 1

org/channel-tui-state.org

@@ -10,9 +10,6 @@ All state mutation flows through event handlers in the controller.
 
 1. (init-state): returns a fresh state plist with ~:msgs~ list,
    ~:input~ buffer, ~:dirty~ flag, ~:busy~ flag, and ~:connection~ status.
-   v0.7.0: ~:scroll-at-bottom~ flag tracks whether the user is scrolled to
-   the bottom. ~add-msg~ sets ~:scroll-notify~ t when a new message arrives
-   and the user is scrolled up.
 2. (add-msg role content &key gate-trace): appends a message object
    to the ~:messages~ vector (v0.3.3), tagged with timestamp, role,
    and optional gate-trace from the daemon (v0.4.0).
@@ -135,8 +132,6 @@ See *tui-theme-presets* for named presets (dark, light, solarized, gruvbox).")
               :input-buffer nil :input-history nil :input-hpos 0
               :messages (make-array 16 :adjustable t :fill-pointer 0)
               :scroll-offset 0 :busy nil :cursor-pos 0
-              :pending-ctrl-x nil :scroll-at-bottom t
-              :scroll-notify nil)
               :dirty (list nil nil nil))))
 #+end_src
 
@@ -171,9 +166,6 @@ See *tui-theme-presets* for named presets (dark, light, solarized, gruvbox).")
 
 (defun add-msg (role content &key gate-trace)
   (vector-push-extend (list :role role :content content :time (now) :gate-trace gate-trace) (st :messages))
-  ;; v0.7.0: if scrolled up, set notification flag
-  (unless (st :scroll-at-bottom)
-    (setf (st :scroll-notify) t))
   (setf (st :dirty) (list t t nil)))
 #+end_src