fix(wizard): resolve skills sync script path (#690)

docs/scratchpads/B2-skills-sync-path.md

@@ -0,0 +1,34 @@
+# B2 — Fresh-install skills sync path
+
+## Problem
+
+Greenfield wizard on `next` reported:
+
+```text
+Skills sync script not found at ~/.config/mosaic/bin/mosaic-sync-skills
+Skills: install failed
+```
+
+## Diagnosis
+
+The framework install migration removed the legacy `~/.config/mosaic/bin/` directory and now installs framework helper scripts under:
+
+```text
+~/.config/mosaic/tools/_scripts/
+```
+
+`packages/mosaic/src/stages/finalize.ts` still resolved wizard helper scripts from `mosaicHome/bin`, so wizard-selected skills failed even though `mosaic-sync-skills` was present in the current framework layout.
+
+## Fix
+
+- Resolve framework helper scripts through `tools/_scripts/<name>` first.
+- Keep a legacy `bin/<name>` fallback for pre-migration installs.
+- Point missing-script warnings at the current `tools/_scripts` layout.
+- Update the finalize skills test fixture to model the fresh framework layout.
+- Update framework README examples from legacy `bin/` helper paths to `tools/_scripts/`.
+
+## Verification
+
+- Unit: `pnpm --filter @mosaicstack/mosaic test -- finalize-skills`
+- Gates: `pnpm typecheck`, `pnpm lint`, `pnpm format:check`, `pnpm build`
+- Fresh path: ran `packages/mosaic/framework/install.sh` with a temp `MOSAIC_HOME` and `MOSAIC_SYNC_ONLY=1`; verified `tools/_scripts/mosaic-sync-skills` exists, legacy `bin/mosaic-sync-skills` does not, and the script installs a selected fake `lint` skill into Mosaic + Pi runtime skill directories.