Validator mirrors for launcher-surfaced classification gaps

The root launcher migration (see roadmap/changelog.md when its item lands) surfaced two classifier-side invariants with no validate-time twin, both recorded on that item’s slice logs and both cheap to close now that the launcher relation single-sources the relevant populations. (1) is closed: the deterministic-order rule used to skip the root @routine chain, first by capability non-membership and later by an explicit carve-out on the source axis, and roadmap/routine-composition-surface-from-facts.md removed the carve-out rather than re-sourcing the rule off the launcher relation. A routine-backed list now fails the build unless it names an order, with a message forked on terminus kind. (2) A GraphitronType.TableInterfaceType participant without @discriminator classifies and renders the legacy silent shape (its projection contributes but its rows are unroutable and its gated JOIN arms are skipped), guarded only by one documented renderer gate in render/DiscriminatedTableFragments; the honest fix is a parse-time rejection (or validator drain) so the shape fails the build instead of returning rows the TypeResolver cannot route. Related enforcement seams to keep aligned: GraphitronSchemaValidator.validateJoinedTableReprojection (the joined-table reprojection fold’s deferral drain) and the TypeBuilder.buildParticipantList rejection for classified non-table members of a discriminated interface, which has no reaching SDL fixture yet (an @error implementor is the nearest shape) and deserves one when this item lands.

(3) Deferred here from the command programme’s DML slice per its design record: the declared-but-unpopulated Operation arms (UpdateMatching, DeleteMatching, EntityResolve, Count, Facet) owe a per-arm answer to "does a schema reaching the arm get a validate-time rejection" (the validator-mirror rule). The matching pair’s current state: no classifier path constructs either arm (condition-matched UPDATE / DELETE are unimplemented behaviour, category (a) in the exemption-list triage), so no schema reaches them and no rejection can fire; the per-arm answer to record when this item lands is either a located rejection at the SDL surface that would classify onto them, or a statement that the surface itself is unparseable today so unreachability is structural. Count / Facet are synthesised (no SDL origin; the connection promoter mints them), and EntityResolve rides the federation surface; each needs the same one-sentence verdict.