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/analysis-ordering.md

@@ -0,0 +1,40 @@
+---
+id: analysis/ordering
+name: Implement execution ordering functions (topologicalOrder, parallelGroups, criticalPath, reachableFrom)
+status: pending
+depends_on:
+  - graph/flowgraph-class
+  - graph/queries
+scope: narrow
+risk: low
+impact: component
+level: implementation
+---
+
+## Description
+
+Implement the standalone analysis functions for execution ordering. These are pure functions operating on FlowGraph instances, delegating to graphology-dag algorithms.
+
+## Acceptance Criteria
+
+- [ ] `topologicalOrder(graph: FlowGraph): string[]` — uses graphology-dag topologicalSort, throws CycleError on cycles
+- [ ] `parallelGroups(graph: FlowGraph): string[][]` — groups by dependency depth (group 0 = roots, group 1 = dependents of group 0, etc.)
+- [ ] `criticalPath(graph: FlowGraph): string[]` — longest path through DAG
+- [ ] `reachableFrom(graph: FlowGraph, nodeIds: string[]): Set<string>` — BFS/DFS from starting nodes
+- [ ] `ancestors(graph: FlowGraph, nodeId: string): string[]` and `descendants(graph: FlowGraph, nodeId: string): string[]`
+- [ ] All functions are standalone (not FlowGraph methods), in `src/analysis/`
+- [ ] O(V + E) complexity for all — documented in JSDoc
+- [ ] Unit tests: known DAGs produce expected orderings, parallel groups, critical paths
+
+## References
+
+- docs/architecture/analysis.md — execution ordering functions, performance characteristics
+- docs/architecture/flowgraph-api.md — convenience delegation from FlowGraph to standalone functions
+
+## Notes
+
+> To be filled by implementation agent
+
+## Summary
+
+> To be filled on completion