chore: remove Codecov flags and simplify coverage upload

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: mpyw

.github/workflows/ci.yml

@@ -31,23 +31,11 @@ jobs:
       - name: Run e2e tests with coverage
         run: go test -v -race -coverprofile=coverage-e2e.txt -covermode=atomic -coverpkg=./... ./e2e/...
 
-      - name: Upload unit test coverage to Codecov
+      - name: Upload coverage to Codecov
         uses: codecov/codecov-action@v5
         with:
           token: ${{ secrets.CODECOV_TOKEN }}
-          files: ./coverage-unit.txt
-          flags: unit
-          disable_search: true
-          verbose: true
-
-      - name: Upload e2e test coverage to Codecov
-        uses: codecov/codecov-action@v5
-        with:
-          token: ${{ secrets.CODECOV_TOKEN }}
-          files: ./coverage-e2e.txt
-          flags: e2e
-          disable_search: true
-          verbose: true
+          files: ./coverage-unit.txt,./coverage-e2e.txt
 
   lint:
     name: Lint

codecov.yml

@@ -9,16 +9,7 @@ coverage:
         target: auto
         threshold: 1%
 
-flag_management:
-  default_rules:
-    carryforward: true
-  individual_flags:
-    - name: unit
-      carryforward: true
-    - name: e2e
-      carryforward: true
-
 comment:
-  layout: "reach, diff, flags, files"
+  layout: "reach, diff, files"
   behavior: default
   require_changes: false