fix: resolve golangci-lint findings (errcheck 3, staticcheck 2)

- r2.go: explicitly ignore deferred resp.Body.Close() errors (3x errcheck)
- handler_test.go: use typed nil context var to preserve the intentional
  nil-tolerance test while satisfying SA1012
- checks_test.go: convert fakePinger to fakeResult instead of struct literal (S1016)

Mechanical lint fixes only — no behavior change. golangci-lint clean,
go build/vet/test -short all green.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: mastermanas805

logctx/handler_test.go

@@ -119,7 +119,10 @@ func TestHandler_NilCtx(t *testing.T) {
 		}
 	}()
 	// Pass an explicitly nil context. The handler must treat it as empty.
-	if err := h.Handle(nil, newRecord("hello")); err != nil {
+	// Use a typed nil var (not a literal nil) so SA1012 doesn't flag this
+	// intentional nil-tolerance test.
+	var nilCtx context.Context
+	if err := h.Handle(nilCtx, newRecord("hello")); err != nil {
 		t.Fatalf("Handle: %v", err)
 	}
 	rec := decode(t, buf)

readiness/checks_test.go

@@ -163,7 +163,7 @@ func TestMustDuration(t *testing.T) {
 
 type fakePinger struct{ err error }
 
-func (f fakePinger) Ping(ctx context.Context) readiness.PingResult { return fakeResult{f.err} }
+func (f fakePinger) Ping(ctx context.Context) readiness.PingResult { return fakeResult(f) }
 
 type fakeResult struct{ err error }
 

storageprovider/r2/r2.go

@@ -223,7 +223,7 @@ func (p *Provider) issueLongLivedKey(ctx context.Context, in storageprovider.Iss
 	if err != nil {
 		return nil, fmt.Errorf("r2.issueLongLivedKey: do request: %w", err)
 	}
-	defer resp.Body.Close()
+	defer func() { _ = resp.Body.Close() }()
 	respBody, _ := io.ReadAll(resp.Body)
 	if resp.StatusCode >= 400 {
 		return nil, fmt.Errorf("r2.issueLongLivedKey: %d: %s", resp.StatusCode, string(respBody))
@@ -284,7 +284,7 @@ func (p *Provider) issueTempCreds(ctx context.Context, in storageprovider.IssueR
 	if err != nil {
 		return nil, fmt.Errorf("r2.issueTempCreds: do request: %w", err)
 	}
-	defer resp.Body.Close()
+	defer func() { _ = resp.Body.Close() }()
 	respBody, _ := io.ReadAll(resp.Body)
 	if resp.StatusCode >= 400 {
 		return nil, fmt.Errorf("r2.issueTempCreds: %d: %s", resp.StatusCode, string(respBody))
@@ -343,7 +343,7 @@ func (p *Provider) RevokeTenantCredentials(ctx context.Context, keyID string) er
 	if err != nil {
 		return fmt.Errorf("r2.RevokeTenantCredentials: do request: %w", err)
 	}
-	defer resp.Body.Close()
+	defer func() { _ = resp.Body.Close() }()
 	if resp.StatusCode == http.StatusNotFound {
 		// Key already gone — idempotent.
 		return nil