intent: with sourceStatus:, a voided target frees the one-shot slot but nothing can re-fire the event-driven create-from

[delchev]

#6814 / #6850 made the event-driven create-from's at-most-once guard state-aware: a target retired to a cancelled/void stage is stepped over, so "void and reissue" became expressible - the next qualifying event (or a click) mints the replacement.

With sourceStatus: the "next qualifying event" cannot exist. The first generation's completion hook flips the source to its post-generation status (Generate.java.template:150-165, updateProperty(sourceId, "<statusProperty>", <value>)) - deliberately, so the guard-claimed source stops matching. But the trigger is event: { onTransition: <Source>, when: "Status == <pre-generation status>" }, and the flipped source will not transition through that status again (the usual lifecycle graph declares no edge back). So after voiding the target:

• the guard correctly steps over the retired document - the slot is FREE;
• nothing ever fires into it - the source sits at the post-generation status and re-emits no qualifying -transitioned;
• only a shared button: true can reissue. An event-only rule (button: false, the shape intent: event-driven generates - create a document from a source document on an entity event, not only a button #6711 introduced the axis for) has NO reissue path at all.

For the sourceStatus: combination #6850 half-delivers: the door is unlocked and nobody can knock.

Directions worth weighing:

• the target's retiring transition re-delivers the source's qualifying event (the void is the business moment that reopens the slot - but it crosses from the target's lifecycle into the source's topic);
• a declared reopen: voiding the target flips the source BACK (the completion hook's inverse), so the ordinary re-transition path re-fires - explicit in the model, uses only existing vocabulary;
• or document that sourceStatus: + event-only requires button: true for reissue, and have the parser warn on the silent combination (event-only + sourceStatus + a classified nomenclature), the same posture fix(intent): a voided target no longer blocks its replacement (#6814) #6850 took for the unclassified one.

Follow-up to #6850; composes with #6859's guard-ownership rule (one rule owns the slot either way).