chore: add codecov configuration

Signed-off-by: Nathan Klick <[email protected]>

codecov.yml

@@ -0,0 +1,21 @@
+codecov:
+  max_report_age: off
+  require_ci_to_pass: true
+comment:
+  behavior: default
+  layout: reach,diff,flags,tree,reach
+  show_carryforward_flags: false
+coverage:
+  precision: 2
+  range:
+    - 60.0
+    - 80.0
+  round: down
+  status:
+    changes: false
+    default_rules:
+      flag_coverage_not_uploaded_behavior: include
+    patch: true
+    project: true
+github_checks:
+  annotations: true