Some bug fixes:

- logging: LogToFile shadowed the package-level fileLogger, so
  IsFileLogger was always false and Shutdown never closed the file
- logging: replace IsJSONHandler's unsafe reflection into slog
  internals with a *slog.JSONHandler type check
- cli: fail if the log file can't be opened instead of silently
  logging to the terminal; return the log shutdown error from Finish
- build.sh: -X flags used the wrong module path, so the version, build
  time and commit were never stamped

internal/config/load_test.go

@@ -32,7 +32,7 @@ func initDir(t *testing.T, env []string, config string) string {
 
 func writeFile(t *testing.T, path, contents string) {
 	t.Helper()
-	if err := os.WriteFile(path, []byte(contents), 0o644); err != nil {
+	if err := os.WriteFile(path, []byte(contents), 0o600); err != nil {
 		t.Fatal(err)
 	}
 }