fix(tests): handle all Close() and Decode() errors across integration tests

Replace all unhandled resp.Body.Close() calls throughout the test suite:

- Deferred calls: replace 'defer VAR.Body.Close()' with a closure that explicitly
  discards the error via 'defer func(Body io.ReadCloser) { _ = Body.Close() }(VAR.Body)'
- Immediate calls: replace 'VAR.Body.Close()' with '_ = VAR.Body.Close()'

Replace all unhandled json.NewDecoder(VAR.Body).Decode(&x) calls with error capture
and require.NoError assertion. Files using httptest.ResponseRecorder (collections_preview,
processing_issues) use 'err :=' declaration; suite-style tests (scanner_integration,
dashboard_integration) use s.T() instead of t.

cmd/server/tests/seven_day_session_test.go

@@ -36,7 +36,9 @@ func TestSevenDaySession(t *testing.T) {
 		client := &http.Client{}
 		resp, err := client.Do(req)
 		require.NoError(t, err)
-		defer resp.Body.Close()
+		defer func(Body io.ReadCloser) {
+			_ = Body.Close()
+		}(resp.Body)
 
 		assert.Equal(t, http.StatusOK, resp.StatusCode)
 
@@ -81,12 +83,15 @@ func TestSevenDaySession(t *testing.T) {
 
 		loginResp, err := http.DefaultClient.Do(loginHTTP)
 		require.NoError(t, err)
-		defer loginResp.Body.Close()
+		defer func(Body io.ReadCloser) {
+			_ = Body.Close()
+		}(loginResp.Body)
 
 		require.Equal(t, http.StatusOK, loginResp.StatusCode)
 
 		var loginResult map[string]interface{}
-		json.NewDecoder(loginResp.Body).Decode(&loginResult)
+		err = json.NewDecoder(loginResp.Body).Decode(&loginResult)
+		require.NoError(t, err)
 
 		refreshToken, ok := loginResult["refresh_token"].(string)
 		require.True(t, ok, "Should have refresh_token")
@@ -103,12 +108,15 @@ func TestSevenDaySession(t *testing.T) {
 
 		refreshResp, err := http.DefaultClient.Do(refreshHTTP)
 		require.NoError(t, err)
-		defer refreshResp.Body.Close()
+		defer func(Body io.ReadCloser) {
+			_ = Body.Close()
+		}(refreshResp.Body)
 
 		assert.Equal(t, http.StatusOK, refreshResp.StatusCode)
 
 		var refreshResult map[string]interface{}
-		json.NewDecoder(refreshResp.Body).Decode(&refreshResult)
+		err = json.NewDecoder(refreshResp.Body).Decode(&refreshResult)
+		require.NoError(t, err)
 
 		// Verify ExpiresIn is 7 days
 		expiresIn, ok := refreshResult["expires_in"].(float64)
@@ -134,7 +142,9 @@ func TestSevenDaySession(t *testing.T) {
 
 		resp, err := http.DefaultClient.Do(req)
 		require.NoError(t, err)
-		defer resp.Body.Close()
+		defer func(Body io.ReadCloser) {
+			_ = Body.Close()
+		}(resp.Body)
 
 		var authResponse struct {
 			Token string `json:"access_token"`
@@ -230,7 +240,7 @@ func TestNoClientSideCookies(t *testing.T) {
 
 		resp, err := http.DefaultClient.Do(req)
 		require.NoError(t, err)
-		resp.Body.Close()
+		_ = resp.Body.Close()
 
 		// Accept both 201 (new user) and 409 (already exists from previous run)
 		require.True(t, resp.StatusCode == http.StatusCreated || resp.StatusCode == http.StatusConflict,
@@ -253,7 +263,9 @@ func TestNoClientSideCookies(t *testing.T) {
 
 			resp2, err := http.DefaultClient.Do(req2)
 			require.NoError(t, err)
-			defer resp2.Body.Close()
+			defer func(Body io.ReadCloser) {
+				_ = Body.Close()
+			}(resp2.Body)
 
 			body, err := io.ReadAll(resp2.Body)
 			require.NoError(t, err)
@@ -277,7 +289,9 @@ func TestNoClientSideCookies(t *testing.T) {
 
 		loginResp, err := http.DefaultClient.Do(loginReq)
 		require.NoError(t, err)
-		defer loginResp.Body.Close()
+		defer func(Body io.ReadCloser) {
+			_ = Body.Close()
+		}(loginResp.Body)
 
 		assert.Equal(t, http.StatusOK, loginResp.StatusCode)