show secrets and configs details in service inspect --pretty

[knQzx]

summary

• show config/secret ID, UID, GID, and file mode in pretty-print output for docker service inspect --pretty
• handle runtime configs that have no file target without panicking (shows [runtime] instead)
• add test for runtime config rendering in pretty-print

test plan

• ran full unit test suite for cli/command/service/ - all 72 tests pass
• updated golden file for pretty-print output
• added TestPrettyPrintWithRuntimeConfig to verify runtime configs render correctly
• verified existing TestPrettyPrintWithConfigsAndSecrets still passes with new ID assertions

fixes #908