v0.7.2: context visibility (/context) — TDD

/context shows message count, focus, token estimate, and last 5
message summaries. Inline command, no daemon interaction needed.

- channel-tui-main: /context handler, 1 test
- Fixed /tags handler (removed dangling else clause)
- TUI Main: 84/85 (1 pre-existing core flake)

org/channel-tui-main.org

@@ -195,13 +195,31 @@ Event handlers + daemon I/O + main loop.
                              (add-msg :system (format nil "Node ~a not found" node-id))))
                        (add-msg :system "Memory audit not available")))
                   ;; /tags command — tag stack
+                  ;; /tags command — tag stack
                   ((string-equal text "/tags")
-                   (let ((cats (or passepartout::*tag-categories* nil)))
-                         (if cats
-                             (dolist (entry cats)
-                               (add-msg :system (format nil "~a: ~a" (car entry) (cdr entry))))
-                             (add-msg :system "No tags configured. Set TAG_CATEGORIES env var.")))
-                       (add-msg :system "Tag categories not loaded")))
+                   (let ((cats passepartout::*tag-categories*))
+                     (if cats
+                         (dolist (entry cats)
+                           (add-msg :system (format nil "~a: ~a" (car entry) (cdr entry))))
+                         (add-msg :system "No tags configured. Set TAG_CATEGORIES env var."))))
+                  ;; /context command — context visibility
+                  ((string-equal text "/context")
+                   (let* ((msg-count (length (st :messages)))
+                          (focus (or (st :foveal-id) "none"))
+                          (est-tokens (min 8192 (* msg-count 50))))
+                     (add-msg :system (format nil "Context: ~d msgs, focus=~a, est ~d/8192 tokens"
+                                             msg-count focus est-tokens))
+                     (let ((start (max 0 (- msg-count 5))))
+                       (loop for i from start below msg-count
+                             for m = (aref (st :messages) i)
+                             for content = (getf m :content)
+                             for preview = (if (> (length content) 50)
+                                              (concatenate 'string (subseq content 0 47) "...")
+                                              content)
+                             for role = (getf m :role)
+                             do (add-msg :system (format nil "  ~a: ~a"
+                                                         (case role (:user "You") (:agent "Agent") (t "Sys"))
+                                                         preview))))))
                   ((string-equal text "/help")
                    (add-msg :system
                     "/focus <proj>  Set project context")