fix(display): Vegas teardown and 240s default; remove dead Vegas buffer code (#637)

* fix(display): tear down Vegas mode on controller cleanup

DisplayController.cleanup() never called VegasModeCoordinator.cleanup(),
so the Vegas teardown (stop, pipeline/stream reset, adapter cache drop)
was unreachable. Call it before the display manager is cleaned up, and
skip it when Vegas was never created.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* fix(vegas): default max_cycle_duration to the documented 240s

The template, the web UI help, CONFIG_REFERENCE and the controller all
say 240, but the code defaulted to 600 in two places, so a config
without the key ran Vegas iterations 2.5x longer than documented.

from_config now falls back to the dataclass field defaults instead of
repeating each one, so the two copies can no longer drift, and the
controller's follower scroll-speed default reads VegasModeConfig's.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* fix(display): let run.py -d show display_manager's DEBUG output

display_manager pinned its logger to INFO at import, overriding the root
level, so debug mode never showed its DEBUG lines. Use get_logger() from
src.logging_config like the rest of the core and leave the level to the
logging setup.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* fix(display): run each startup validation check once

StartupValidator.validate_all() ran twice at boot, before and after the
plugin manager was created, so every config, cache, display and
systemd-unit warning was logged twice. The second pass now runs only the
plugin checks. Drop the commented-out raise_on_errors line.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* fix(vegas): one INFO line per plugin-list refresh

StreamManager logged "=" * 60 banners and a line per plugin (INCLUDED,
SKIPPED, FETCHING CONTENT, SEGMENT CREATED) at INFO on every refresh and
fetch, i.e. at each cycle start and every 30s. Log one INFO summary of
the rotation per refresh and move the per-plugin detail, the weighting
breakdown and "no content this cycle" to DEBUG (the adapter still warns
when every content path fails).

Also drop the check/cross marks from the controller's log messages.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* fix(vegas): drop the per-iteration static-mode plugin scan

run_iteration() rebuilt _static_mode_plugins on every iteration, asking
every plugin for its display mode and logging the set at INFO, but
nothing ever read it: static pauses are triggered by
_check_static_plugin_trigger() from the next segment. Delete it, the
coordinator's get_ordered_plugins() that only it used, and the
write-only _static_pause_plugin / _static_pause_start.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* fix(vegas): remove the staging buffer that was never filled

StreamManager and RenderPipeline carried a double-buffer design that
nothing used: _staging_buffer was only ever cleared or swapped, so
swap_buffers() never did anything and should_recompose()'s
staging_count > 0 branch was dead, and _active_scroll_image,
_staging_scroll_image, _is_rendering, _last_frame_time and
_frame_interval were written but never read. Delete the machinery and
rewrite the docstrings around what actually carries updates:
_pending_updates, consumed by process_updates() in swap mode and
invalidate_pending_updates() in continuous mode.

should_recompose() no longer builds a buffer-status dict every frame.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* refactor(display): tidy the display controller without changing behaviour

- Import VegasModeCoordinator locally instead of through module globals
  (there is no circular import to avoid).
- Drop hasattr() checks on attributes PluginManager.__init__ always sets
  (plugin_executor, plugin_last_update, get_plugin_lock,
  run_scheduled_updates*, stop_update_worker) and the dead "older
  manager" fallbacks; keep the health_tracker None checks, now via
  _health_tracker().
- Extract _display_once() for the per-frame display call both render
  loops copied, _advance_on_demand() for the two on-demand rotations,
  _reset_on_demand_fields() for the error and clear paths, and
  _timezone() / _in_window() for the two schedule checks.
- Remove always-true conditions and the unreachable non-plugin else
  branch in run(), and read _was_display_active / _last_published_mode /
  vegas_coordinator directly now that __init__ declares them.
- Declare the follower render state in __init__, name its tuning
  constants, add _follower_sign(), and share the 90/s sync send
  interval with the render pipeline (SYNC_SEND_INTERVAL).
- Delete history narration and the "Opt #N" labels, fix the comment
  that called _scroll_speed constant (hot reload updates it), and drop
  a startup timing log that measured nothing.
- render_pipeline / plugin_adapter: read display_manager.width/height
  as the properties they are, drop an empty TYPE_CHECKING block, an
  aliased threading import and a duplicated `if result and
  self.sync_manager:`.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* refactor(display): trim dead code from display_manager

- Add _new_canvas() for the image/draw/fontmode="1" setup that was
  copied six times.
- Call resolve_double_sided() and compose_pixel_mapper_config() directly
  instead of through a module alias and a passthrough method, and replace
  the comment that said the passthrough read class attributes.
- Delete the unused _initialized flag and _ORIENTATION_ROTATE_DEGREES
  alias (no core or monorepo reader; tests stop resetting the flag), the
  test pattern's unreachable no-matrix branch (it only runs once the
  matrix exists), `del old_image  # help GC` (a no-op on a local), a
  duplicated early return in process_deferred_updates, and stale
  comments.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* refactor(vegas): remove unread fields and test-only helpers, fix docstrings

- ContentSegment: drop total_width, fetched_at, is_stale, image_count and
  is_static, none of which is read.
- StreamManager: drop _current_index (never advanced) and the test-only
  get_all_content_for_composition() and has_pending_updates();
  VegasModeConfig: drop the test-only is_plugin_included().
- geometry.find_blank_cut() has had no production caller since the crop
  moved to item boundaries; delete it and its tests.
- PluginAdapter: the _finalize docstring described separator_width
  between every image, and _crop_to_budget's said cuts snap to the
  nearest blank column; both now describe what the code does.
- Coordinator: the static-pause interrupt log no longer blames follower
  mode for every interrupt, and set_update_callback names the callback
  the controller actually wires.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* refactor(scroll): correct ScrollHelper comments and drop dead branches

- Four comments said the strip always starts with display_width of
  blank; it does only when lead_gap is None (Vegas passes its own).
- Delete the "Width calculation mismatch" warning: the image is created
  at the calculated width, so the two can never differ.
- Remove the two scroll_delay <= 0 fallbacks (which disagreed with each
  other): set_scroll_delay clamps it to at least 0.001 and nothing in
  core or the plugin monorepo assigns it directly.
- Trim the scipy history from the blend docstring.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* refactor(run): drop a redundant comment

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* fix(display): log set_scrolling_state only when it changes

Vegas and scrolling plugins set the scrolling state every frame, so once
display_manager's DEBUG output became visible in debug mode it printed
"Scrolling state set to: True" about 120 times a second. Log only when
the value differs from the previous one; the state, activity timestamp
and frame hold still update on every call.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* docs(changelog): display-vegas

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

test/test_vegas_geometry.py

@@ -10,7 +10,6 @@ from src.vegas_mode.geometry import (
     content_bounds,
     dead_window_stats,
     edge_blank,
-    find_blank_cut,
     separation_gap,
     trim_to_content,
     window_coverage_stats,
@@ -320,51 +319,3 @@ class TestSeparationGap:
         # flat gap; measured separation lifts them to the 24px target.
         card = paint(make_img(150), 0, 150)
         assert separation_gap(card, card, target=24, minimum=8) == 24
-
-
-class TestFindBlankCut:
-    def test_snaps_to_the_nearest_gap(self):
-        img = paint(make_img(200), 0, 90)
-        paint(img, 110, 200)
-        # 100 is inside the 90..110 gap already.
-        assert find_blank_cut(img, 100, 20) == 100
-
-    def test_walks_outwards_to_find_a_gap(self):
-        img = paint(make_img(200), 0, 95)
-        paint(img, 105, 200)
-        cut = find_blank_cut(img, 90, 20)
-        assert 95 <= cut < 105
-
-    def test_solid_ink_returns_the_target(self):
-        assert find_blank_cut(paint(make_img(200), 0, 200), 100, 20) == 100
-
-    def test_target_at_image_width_does_not_index_past_the_end(self):
-        # A cut after the last column is legal. Indexing ink[width] raised
-        # IndexError in the field, losing that plugin's content for the cycle.
-        # Reached once the rotation offset advances so start + budget lands
-        # exactly on the image width.
-        img = paint(make_img(1840), 0, 1840)
-        assert find_blank_cut(img, 1840, 32) == 1840
-
-    def test_target_past_image_width_is_clamped(self):
-        img = paint(make_img(100), 0, 100)
-        assert find_blank_cut(img, 500, 32) == 100
-
-    def test_target_at_width_with_a_trailing_gap_snaps_back(self):
-        # Content 0..179, blank 180..199. The nearest blank column to 200 is
-        # 199, not the start of the gap — nearest is what keeps the cut as
-        # close as possible to the requested budget.
-        img = paint(make_img(200), 0, 180)
-        assert find_blank_cut(img, 200, 32) == 199
-
-    def test_zero_radius_returns_the_target(self):
-        assert find_blank_cut(paint(make_img(100), 0, 100), 50, 0) == 50
-
-    def test_negative_target_is_clamped_to_zero(self):
-        assert find_blank_cut(paint(make_img(100), 0, 100), -20, 8) == 0
-
-    @pytest.mark.parametrize("target", [0, 1, 50, 99, 100])
-    def test_never_raises_across_the_range(self, target):
-        img = paint(make_img(100), 0, 100)
-        cut = find_blank_cut(img, target, 16)
-        assert 0 <= cut <= 100