Implement nested optional query fix for Fuseki in SPARQL emission

docs/reports/014-fuseki-nested-optional-query-fix.md

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+# Fuseki Nested-Optional Query Fix
+
+## Summary
+
+This report records the `packages/linked` fix for incorrect LINCD-generated SPARQL against Fuseki. The root cause lived in `src/sparql/irToAlgebra.ts`: nested optional traversals were emitted as sibling `OPTIONAL` blocks, which let Fuseki bind child triples independently from the parent traverse.
+
+The fix keeps nested optional traverses structurally nested and resolves shape/property IDs to ontology IRIs before SPARQL emission.
+
+## What Changed
+
+- root shape scans now resolve to `ShapeClass.targetClass.id`
+- property references now resolve to `PropertyShape.path`
+- nested optional traverses are emitted as nested `OPTIONAL` blocks instead of flattened sibling blocks
+- child properties under optional traverses are prevented from escaping into required triple sets
+
+## Key Behavior
+
+LINCD usage such as:
+
+```ts
+e.image.select((img) => [img.contentUrl])
+```
+
+now produces SPARQL shaped like:
+
+```sparql
+OPTIONAL {
+  ?event schema:image ?image .
+  OPTIONAL {
+    ?image schema:contentUrl ?contentUrl .
+  }
+}
+```
+
+instead of:
+
+```sparql
+OPTIONAL { ?event schema:image ?image . }
+OPTIONAL { ?image schema:contentUrl ?contentUrl . }
+```
+
+## Validation
+
+- `cd packages/linked && yarn build`
+- cross-repo runtime verification confirmed:
+  - active events load correctly again
+  - March/April events no longer inherit incorrect images
+  - Rotary retains its real image
+
+## Related Work
+
+- `packages/lincd.org/docs/reports/001-fuseki-nested-optional-query-fix.md`
+- `packages/the-game/docs/reports/001-fuseki-nested-optional-query-fix.md`
+
+## Wrapup Notes
+
+- no findings were identified for the linked/core implementation
+- a changeset is still needed before PR if linked package release notes are required