feat(dsh): add Guion-compatible managed presets

[orga-agent]

Summary

• make the Guion DSH bundle own the complete web research tool surface
• add web dsh sync and web dsh doctor for compatible standard, ptc, cordis, and minimal presets
• hide shipped presets while retaining user presets and require confirmation before replacing modified same-ID content
• remove the official DSH Web runtime dependency and settings surface

Verification

• pnpm test (20 files, 161 tests)
• pnpm typecheck
• pnpm build
• pnpm test:pack
• pnpm format:check
• pnpm test:release
• real NUC DSH Loader validation with a disposable DSH_HOME: all four compositions contain no scoped tool-web; effective web_fetch and web_search schemas verified

No upstream DSH changes or live Yuki/profile mutations are included.