fix build/distribution spec: npm deps not workspace, align configs with sibling projects, resolve review issues

- Replace workspace:* deps with published npm semver ranges (^0.34.49, ^0.1.0)
- Expand package.json: add description, publishConfig, scripts, engines,
  devDependencies, conditional exports with types/default for import+require
- Fix tsup entry names (path-prefixed like ujsx), add target: es2022,
  remove splitting:true (not used by sibling projects)
- Align tsconfig with sibling projects: add lib, noUncheckedIndexedAccess,
  noUnusedLocals, noUnusedParameters, erasableSyntaxOnly, etc.
- Expand vitest.config.ts with include, coverage, and path alias
- Clarify @preact/signals-core as direct dep (not just transitive via ujsx)
- Clarify @alkdev/pubsub is a consumer dependency, not flowgraph's dep
- Fix edge key convention: document composite key format for call graph's
  multi-edge-type scenario (triggered + depends_on between same pair)
- Align OperationEdgeAttrs field naming: use detail+mismatches consistently
  instead of compatibilityDetail
- Add InvalidInputError to error hierarchy (referenced in flowgraph-api but
  was missing)
- Fix undefined attrs.category reference in reactive-execution.md
- Remove internal drafting note from host-configs.md
- Fix ReactiveHostConfig constructor signature inconsistency across docs
- Constrain TemplateEdgeAttrs.edgeType to sequential|conditional only

docs/architecture/README.md

@@ -40,7 +40,7 @@ The operation graph provides static type checking and structural validation. The
 | `@alkdev/ujsx` | **Direct dependency**. Workflow templates are `UNode` trees rendered through `HostConfig`s. Flowgraph provides the workflow-specific host configurations (graphology DAG, reactive execution). |
 | `@alkdev/taskgraph` | **Pattern reference**. Flowgraph follows the same graphology-wrapping pattern (`FlowGraph` class like `TaskGraph` class) but enforces DAG invariants instead of allowing cycles. |
 | `@alkdev/typebox` | **Direct dependency**. All schemas are TypeBox Modules. Runtime validation, JSON Schema export, and `Value.Check`/`Value.Errors`. |
-| `@alkdev/pubsub` | **Optional peer dependency**. For event-driven call graph population. Flowgraph works in-memory; pubsub connects it to the call protocol. |
+| `@alkdev/pubsub` | **Consumer dependency, not flowgraph's dep**. For event-driven call graph population. The hub coordinator uses pubsub to subscribe to call events and feed them to flowgraph — flowgraph itself works in-memory with no pubsub import. |
 | `@alkdev/cograph` | **Future consumer**. The cognitive graph depends on flowgraph for workflow templates and execution tracking. |
 
 ## Current State