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/call-graph.md

@@ -99,7 +99,7 @@ Call graph edges carry an `edgeType` attribute:
 
 `triggered` edges use `${parentRequestId}->${childRequestId}` as the edge key. `depends_on` edges use `${sourceRequestId}->${targetRequestId}:depends_on` to distinguish from `triggered` edges between the same pair.
 
-Since `multi: false`, there can be at most one `triggered` and one `depends_on` edge between the same pair. The edge key convention ensures deterministic keys.
+This composite key format is necessary because `multi: false` allows at most one edge per key between a given (source, target) pair. Since a call graph can have both a `triggered` edge (parent→child) and a `depends_on` edge (data dependency) between the same pair of calls, the edge type suffix in the key disambiguates them. See [schema.md#edge-key-convention](schema.md) for the general key convention and the discussion of multi-edge support.
 
 ## Status Lifecycle