Declaration bundling peaks at ~9 GB on the ontology integration branch #653

Observation

The tsup declaration bundle (dts: true in packages/typegraph/tsup.config.ts) now peaks at about 9.3 GB of resident memory in the DTS worker, measured with /usr/bin/time -l node --max-old-space-size=12288 node_modules/tsup/dist/cli-default.js on the integration branch that combines the ontology and semantics program (acyclic relations, composition, typed subsumption, identity transition log, meta-edge removal). On main the same build fits under 6 GB. The largest emitted chunk grew only from 392 KB to 432 KB over the same span, so output size does not explain a ~50% jump in bundling memory.

The CI ceiling has been raised twice to keep the build running (#643 to 8 GB, #652 to 12 GB). Public runners have 16 GB, so there is one more bump left before the build stops fitting at all.

Suspects

• Deeply nested conditional/mapped types on the public query surface (the polymorphic supertype default and includeNarrower, parts() / wholes() return-type generics) expanding during declaration rollup.
• One dts rollup for every entrypoint re-traversing the same backend and store type graph; per-entrypoint memory is not freed between rollups inside one worker.

Options to evaluate

• experimentalDts: true (TypeScript's own declaration emit plus a lighter rollup) and compare peak RSS.
• Emitting declarations once and rolling entrypoints from that emit rather than from source per entrypoint.
• Measuring which entrypoint's rollup drives the peak (--dts-only per entry) and whether one type family dominates.

The 12 GB ceiling is a stopgap; the fix is to bring the bundle back under the previous ceiling.