remove dead action_buttons module (superseded by action_bar in Phase L)

Deletes src/action_buttons.{h,cpp} and tests/test_action_buttons.cpp;
removes the static library, test target, and reaper_reasampler link
entry from CMakeLists.txt; scrubs all dangling comment references.

CMakeLists.txt

@@ -318,20 +318,6 @@ target_include_directories(provenance PUBLIC src)
 add_library(assignment_request STATIC src/assignment_request.cpp)
 target_include_directories(assignment_request PUBLIC src)
 
-# ---------------------------------------------------------------------------
-# 2k) Pure action_buttons library — NO REAPER, NO SWELL. The Milestone 11
-#     action-trigger button strip: strip rect + N buttons at a minimum width ->
-#     per-button rects (equal tiling; overflow HIDES excess on a narrow panel
-#     rather than clipping), point -> button hit-test, and the button label format
-#     (action name + SDK binding string -> label, with the unbound/blank case
-#     degraded to an explicit marker and an over-long binding truncated). Split out
-#     so the layout + label math is unit-tested outside the DAW; the bank_panel
-#     draw + NamedCommandLookup/Main_OnCommand dispatch + kbd_getTextFromCmd query
-#     are DAW-verified. Mirror of mode_switch / tab_strip.
-# ---------------------------------------------------------------------------
-add_library(action_buttons STATIC src/action_buttons.cpp)
-target_include_directories(action_buttons PUBLIC src)
-
 # ---------------------------------------------------------------------------
 # 2l) Pure drag_out library — NO REAPER, NO SWELL, NO OS/OLE. The Milestone 11
 #     native-OS-drag-out decision core: the gesture-boundary decision (drag state +
@@ -341,7 +327,7 @@ target_include_directories(action_buttons PUBLIC src)
 #     an explicit skip-missing / skip-unresolved policy). Split out so the boundary +
 #     set algebra are unit-tested outside the DAW; the OLE DoDragDrop / SWELL file-list
 #     initiation (drag_out_win) and the bank_panel gesture hook are DAW-verified. Mirror
-#     of action_buttons / mode_switch.
+#     of mode_switch.
 # ---------------------------------------------------------------------------
 add_library(drag_out STATIC src/drag_out.cpp)
 target_include_directories(drag_out PUBLIC src)
@@ -378,7 +364,7 @@ target_include_directories(theme PUBLIC src)
 #     generic component geometry the kit draws against: button box (inset + graceful
 #     suppression), horizontal slider track/handle/filled geometry + value<->px inverse,
 #     and list-row rect + hover hit-test. The kit-level primitives that don't already
-#     have a pure owner (bank_grid/mode_switch/tab_strip/action_buttons/prune_button
+#     have a pure owner (bank_grid/mode_switch/tab_strip/prune_button
 #     stay the source of truth for THEIR surfaces). Names KitBox/KitButtonBox/
 #     SliderGeometry/ListRowBox avoid the existing ButtonRect/CellRect collisions.
 #     Mirror of prune_button — pure, CTest-covered.
@@ -388,15 +374,15 @@ target_include_directories(component_geometry PUBLIC src)
 
 # ---------------------------------------------------------------------------
 # 2o) Pure action_bar library — NO REAPER, NO SWELL, NO LICE. The Phase L (L2)
-#     dock-panel layout redesign core: the TASK-GROUPED action bar geometry that
-#     supersedes the flat M11 action_buttons strip for the panel's action inventory —
-#     clusters (capture / placement / maintenance) tile the bar at a fixed button
+#     dock-panel layout redesign core: the TASK-GROUPED action bar geometry for the
+#     panel's action inventory — clusters (capture / placement / maintenance) tile the
+#     bar at a fixed button
 #     width with intra/inter-cluster gaps, each button carrying a label + keybinding
 #     micro sub-rect, whole trailing buttons dropped (never clipped) on a narrow panel,
 #     and point -> flat action index hit-test. Split out so the layout + hit-test math
 #     is unit-tested outside the DAW; the bank_panel L1-kit draw + NamedCommandLookup/
 #     Main_OnCommand dispatch + kbd_getTextFromCmd query are DAW-verified. Mirror of
-#     mode_switch / action_buttons / prune_button.
+#     mode_switch / prune_button.
 # ---------------------------------------------------------------------------
 add_library(action_bar STATIC src/action_bar.cpp)
 target_include_directories(action_bar PUBLIC src)
@@ -604,10 +590,6 @@ add_executable(provenance_tests tests/test_provenance.cpp)
 target_link_libraries(provenance_tests PRIVATE provenance bank_model)
 add_test(NAME provenance_tests COMMAND provenance_tests)
 
-add_executable(action_buttons_tests tests/test_action_buttons.cpp)
-target_link_libraries(action_buttons_tests PRIVATE action_buttons)
-add_test(NAME action_buttons_tests COMMAND action_buttons_tests)
-
 add_executable(drag_out_tests tests/test_drag_out.cpp)
 target_link_libraries(drag_out_tests PRIVATE drag_out)
 add_test(NAME drag_out_tests COMMAND drag_out_tests)
@@ -928,7 +910,7 @@ add_library(reaper_reasampler MODULE
     src/card_meta.cpp
     src/card_drag.cpp
 )
-target_link_libraries(reaper_reasampler PRIVATE bank_model capture_paths peaks bank_grid mode_switch tab_strip view_mode_model insert_plan render_settings batch_capture tail_control realtime_record bank_book wav_trim owned_manifest prune_reconcile prune_button app_version provenance action_buttons drag_out instrument_drop theme component_geometry action_bar footer_bar overflow_menu mode_enable tooltip card_meta card_drag assignment_request bank_sync)
+target_link_libraries(reaper_reasampler PRIVATE bank_model capture_paths peaks bank_grid mode_switch tab_strip view_mode_model insert_plan render_settings batch_capture tail_control realtime_record bank_book wav_trim owned_manifest prune_reconcile prune_button app_version provenance drag_out instrument_drop theme component_geometry action_bar footer_bar overflow_menu mode_enable tooltip card_meta card_drag assignment_request bank_sync)
 target_include_directories(reaper_reasampler PRIVATE ${SDK_INC} ${WDL_INC})
 # OUTPUT_NAME is channel-derived (Phase V, V4): "reaper_reasampler" (stable, default) or
 # "reaper_reasampler_beta" (beta). REAPER dlopen's any reaper_* module, so both channels'