Add object filter ratio (#2952)

* Add object ratio config parameters

Issue: #2948

* Add config test for object filter ratios

Issue: #2948

* Address review comments

- Accept `ratio` default
- Rename `bounds` to `box` for consistency
- Add migration for new field

Issue: #2948

* Fix logical errors

- field migrations require default values
- `clipped` referenced the wrong index for region, since it shifted
- missed an inclusion of `ratio` for detections in `process_frames`
- revert naming `o[2]` as `box` since it is out of scope!

This has now been test-run against a video, so I believe the kinks are
worked out.

Issue: #2948

* Update contributing notes for `make`

Issue: #2948

* Fix migration

- Ensure that defaults match between Event and migration script
- Deconflict migration script number (from rebase)

Issue: #2948

* Filter objects out of ratio bounds

Issue: #2948

* Update migration file to 009

Issue: #2948

migrations/009_add_object_filter_ratio.py

@@ -0,0 +1,38 @@
+"""Peewee migrations -- 009_add_object_filter_ratio.py.
+
+Some examples (model - class or model name)::
+
+    > Model = migrator.orm['model_name']            # Return model in current state by name
+
+    > migrator.sql(sql)                             # Run custom SQL
+    > migrator.python(func, *args, **kwargs)        # Run python code
+    > migrator.create_model(Model)                  # Create a model (could be used as decorator)
+    > migrator.remove_model(model, cascade=True)    # Remove a model
+    > migrator.add_fields(model, **fields)          # Add fields to a model
+    > migrator.change_fields(model, **fields)       # Change fields
+    > migrator.remove_fields(model, *field_names, cascade=True)
+    > migrator.rename_field(model, old_field_name, new_field_name)
+    > migrator.rename_table(model, new_table_name)
+    > migrator.add_index(model, *col_names, unique=False)
+    > migrator.drop_index(model, *col_names)
+    > migrator.add_not_null(model, *field_names)
+    > migrator.drop_not_null(model, *field_names)
+    > migrator.add_default(model, field_name, default)
+
+"""
+
+import peewee as pw
+from frigate.models import Event
+
+SQL = pw.SQL
+
+
+def migrate(migrator, database, fake=False, **kwargs):
+    migrator.add_fields(
+        Event,
+        ratio=pw.FloatField(default=1.0),  # Assume that existing detections are square
+    )
+
+
+def rollback(migrator, database, fake=False, **kwargs):
+    migrator.remove_fields(Event, ["ratio"])