The front door for everyday work: classifies the request and invokes exactly one bgPDD lane, so you never have to know the lane names. Use when the ask is ordinary and the right lane is not obvious — 'help me with this', 'quick change', 'small fix', 'add a test', 'clean this up', 'can you sort this out', 'I'm not sure which lane', or '/bg <anything>'. Routes only; never does the work itself.
