[KaiEureka]

Built-in workflow helpers currently share one flat directory, obscuring which files implement Duo, Weave, and Reconstruct. Group each workflow and its private helpers into its own package so the complete implementation is easy to find.

Move each existing entry module to its package's __init__.py, preserving its public import path, function and class module identity, registry entries, and serialization paths. Keep prompts and execution logic unchanged. Update internal test imports and both Duo guides with the source reading entry points.

Validation completed includes Ruff, all four import contracts, dependency checks, documentation translation checks, an sdist-to-wheel build, and an isolated installed-wheel probe that imports every built-in module, checks public identities and class serialization, and executes the existing Weave delivery smoke. Independent review approved the exact head and passed 18 installation/discovery tests, including the OCE wrapper import and argument forwarding. GitHub distribution, macOS, browser fixtures, documentation, title, hygiene, and secret checks have passed. The Python 3.10–3.14 CI matrix is running. Focused workflow regressions completed with 426 passed and 4 optional-interpreter skips. The overlapping local full-suite run was interrupted after 1,466 passed and 2 skipped in favor of the five-version CI matrix; it is not claimed as a completed full-suite result.