rename node to dora-image-view

The repository, the Python package, the entrypoint and the manifest name all
now agree. `plot` was carried over from the upstream opencv-plot node and no
longer described anything here, so the module, the class and the environment
variables follow the node:

  dora_plot/         -> dora_image_view/
  dora_plot/plot.py  -> dora_image_view/view.py
  Plot               -> View
  PLOT_WIDTH/HEIGHT  -> VIEW_WIDTH/HEIGHT
  --plot-width/-height -> --view-width/-height

Breaking for anyone wiring `path: dora-plot` or setting PLOT_WIDTH; nothing is
tagged yet.

tests/test_dora_image_view.py

@@ -7,8 +7,8 @@ import numpy as np
 import pytest
 from PIL import Image
 
-from dora_plot import bbox, decode
-from dora_plot.plot import Bboxes, Plot
+from dora_image_view import bbox, decode
+from dora_image_view.view import Bboxes, View
 
 WIDTH, HEIGHT = 12, 8
 
@@ -123,13 +123,13 @@ def test_xywh_is_converted_to_corners():
 
 
 def test_headless_show_draws_without_a_window():
-    plot = Plot(headless=True, text="hello")
-    plot.bboxes = Bboxes(
+    view = View(headless=True, text="hello")
+    view.bboxes = Bboxes(
         corners=np.array([[1.0, 1.0, 5.0, 5.0]]),
         conf=np.array([0.9]),
         labels=np.array(["cat"]),
     )
     frame = np.zeros((32, 32, 3), dtype=np.uint8)
 
-    assert plot.show(frame) is False
+    assert view.show(frame) is False
     assert frame.any(), "the overlays should have marked the frame"