fix(zsh): Tab completion and colby buffer expansion

Fix fzf_default_completion stale pointer after zle -D by setting it to
expand-or-complete before deleting the lazy comp widget. Rebind ^I
explicitly after widget deletion and add safety net in widgets.zsh
after bindkey -e.

Replace colby() function with ^M buffer expansion so the full
copilot --allow-all-tools --allow-all-paths invocation is visible
in terminal history and screen recordings.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

home/.zsh/widgets.zsh

@@ -387,5 +387,22 @@ for line in sys.stdin:
     }
     zle -N _dots_stash_widget
     bindkey '^Y' _dots_stash_widget
+
+    # Restore Tab after bindkey -e
+    if (( ${+widgets[fzf-completion]} )); then
+        bindkey '^I' fzf-completion
+    elif (( ${+widgets[_dots_lazy_comp_widget]} )); then
+        bindkey '^I' _dots_lazy_comp_widget
+    fi
+
+    # Enter: expand colby → full copilot invocation (visible in terminal history)
+    _dots_enter_handler() {
+        if [[ "$BUFFER" == "colby" || "$BUFFER" == "colby "* ]]; then
+            BUFFER="${BUFFER/#colby/copilot --allow-all-tools --allow-all-paths}"
+        fi
+        zle accept-line
+    }
+    zle -N _dots_enter_handler
+    bindkey '^M' _dots_enter_handler
 }
 _dots_load_keybindings