Drop tp-stack's phantom dependency on tp-ops

tp-stack.el required tp-ops but used nothing from it: a whole-word
sweep of every symbol tp-ops defines finds exactly one hit in
tp-stack, and it is a docstring cross-reference to tp-set, not code.
The require only made the module graph look denser than it is and
suggested a stack->ops edge that never existed.

The stack module's real dependencies are tp-core (interval walking),
tp-reactive (the buffer registry it feeds via
tp-reactive--register-layer-buffer) and tp-layer (the stack-storage
codec).  All three requires are already present, and tp-stack.el
byte-compiles independently with warnings-as-errors after the
deletion.  Load order through tp.el is unaffected.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

tp-stack.el

@@ -22,7 +22,6 @@
 (require 'tp-core)
 (require 'tp-reactive)
 (require 'tp-layer)
-(require 'tp-ops)
 
 ;;; Shared argument parsing and region iteration