fix(api): narrow dataflow dependency ownership

[wolfy-j]

Summary

• remove namespace-wide ownership declarations from Dataflow API entries; imports, router, and function references remain the dependency graph
• retain strict structured finish validation present in the current Hub package
• update the test harness to current workspace and framework dependencies
• reconcile Git release metadata with the already-published Hub 0.7.14 baseline so the next release is 0.7.15

Verification

• make test: 972 tests passed
• make lint: 168 entries checked, no errors (one pre-existing analysis convergence warning)
• SQLite and PostgreSQL GitHub suites pass
• publish dry-run for wippy/dataflow@0.7.15 succeeded
• unpacked Hub 0.7.14 compared against this source; the only unpublished runtime delta is the retained finish-schema validation

This lets obsolete contracts be removed without a surviving API entry claiming the entire userspace.dataflow namespace.