decompose architecture into 38 atomic tasks across 12 parallel generations

Decompose the reviewed architecture specs into taskgraph-managed tasks:
- 2 setup tasks (project init, test infrastructure)
- 4 schema tasks (enums, node attrs, edge attrs, graph schemas)
- 1 error hierarchy task
- 6 graph tasks (FlowGraph class, 3 construction paths, queries, validation)
- 5 analysis tasks (type-compat, build-type-edges, ordering, template-validation, defaults)
- 5 component tasks (Operation, Sequential, Parallel, Conditional, Map)
- 2 host config tasks (GraphologyHostConfig, ReactiveHostConfig)
- 4 reactive tasks (WorkflowRoot, node-status, max-concurrency, retry-semantics)
- 3 review tasks (foundation, reactive-and-hosts, complete-library)
- 5 meta cluster tasks (schema, graph, component, reactive, analysis layers)
- 1 API exports task

Validated with taskgraph: zero cycles, 38 tasks, 12 parallel generations.
Critical path: 12 tasks through reactive execution layer.

tasks/graph-queries.md

@@ -0,0 +1,45 @@
+---
+id: graph/queries
+name: Implement graph query methods (topologicalOrder, ancestors, descendants, call graph queries)
+status: pending
+depends_on:
+  - graph/flowgraph-class
+scope: moderate
+risk: low
+impact: component
+level: implementation
+---
+
+## Description
+
+Implement the query methods on FlowGraph that delegate to graphology and graphology-dag, plus the call-graph-specific observability queries.
+
+## Acceptance Criteria
+
+- [ ] `topologicalOrder(): string[]` — delegates to `graphology-dag.topologicalSort`, throws `CycleError` if cycles exist (should never happen after validated construction)
+- [ ] `hasCycles(): boolean` — delegates to `graphology-dag.hasCycle`
+- [ ] `findCycles(): string[][]` — delegates to graphology cycle detection (debugging)
+- [ ] `ancestors(nodeId): string[]` — delegates to `graphology-dag.ancestors`
+- [ ] `descendants(nodeId): string[]` — delegates to `graphology-dag.descendants`
+- [ ] `predecessors(nodeId): string[]` — delegates to `graph.inNeighbors`
+- [ ] `successors(nodeId): string[]` — delegates to `graph.outNeighbors`
+- [ ] `reachableFrom(nodeIds): Set<string>` — custom BFS/DFS traversal from starting nodes
+- [ ] Call graph queries: `filterByStatus(status): string[]`, `getRoots(): string[]`, `children(requestId): string[]`, `duration(requestId): number`, `lineage(requestId): string[]`
+- [ ] `filterByStatus`: O(n) filter over `forEachNode()` — documented as sufficient for expected sizes
+- [ ] `getRoots()`: returns nodes with `parentRequestId === undefined`
+- [ ] `lineage()`: ancestor chain from root to target
+- [ ] Unit tests for each query method with known graph structures
+
+## References
+
+- docs/architecture/flowgraph-api.md — query methods, call graph queries
+- docs/architecture/operation-graph.md — query delegation to graphology-dag
+- docs/architecture/call-graph.md — observability queries
+
+## Notes
+
+> To be filled by implementation agent
+
+## Summary
+
+> To be filled on completion