fix(packaging): ship bundled skills in the wheel via setup.py data_files

[Que0x]

Problem

Wheel installs shipped zero bundled skills. setup.py generates data_files for skills/ + optional-skills/, but pyproject's [tool.setuptools.data-files] table silently overrides it — setuptools resolves that field from one source, never both. So _get_bundled_dir() finds nothing and sync_skills() returns total_bundled: 0 on every wheel/sealed install. The earlier 3a7ed7be0 ("ship bundled skills in wheel") never actually took effect.

Fix

Make setup.py the single source of truth: dynamically generate data_files for all four bundled dirs (skills, optional-skills, locales, optional-mcps) and remove the shadowing pyproject table. Side fixes in the generator: emit POSIX path separators (was baking in backslash targets), exclude index-cache/__pycache__/*.pyc cruft, and auto-include the silently-dropped optional-mcps/unreal-engine.

Tests

• Wheel rebuilt + inspected: skills/ 447 files / 72 SKILL.md, optional-skills/ 444 / 101, locales/ 16, optional-mcps/ 3 — nested structure preserved, no cruft (before: skills/optional-skills = 0). sdist unchanged (still ships skills via MANIFEST).
• pytest tests/test_packaging_metadata.py → 11 passed (rewrote the locale test for the new source; added 3 regressions: skills completeness/no-flatten/no-cruft, optional-mcps drift guard, pyproject-shadow guard).
• ruff check setup.py tests/test_packaging_metadata.py → clean.

[teknium1]

Thanks for tracing this to the competing setuptools configuration sources. The premise still holds on current main: setup.py:83-86 supplies skill trees through data_files, while pyproject.toml:315-336 declares a separate [tool.setuptools.data-files] table. The packaged-install resolution path consumes <sysconfig data>/skills before source fallbacks (hermes_constants.py:206-223), and sync_skills() returns total_bundled: 0 when that directory is absent (tools/skills_sync.py:505-511).

The PR's single dynamic generator preserves per-directory targets, includes the existing locales and MCP catalog payloads, and its proposed tests cover source completeness, target layout, excluded artifacts, and reintroduction of the shadowing table. No verified correctness issue was found in the diff. The affected packaging sections have not materially changed on current main, so salvage should be mechanical.

Automated hermes-sweeper review.