Move package scripts into packages tree

- relocate Bun normalization helpers under `packages/scripts`
- update shared package build logic to use the new paths
- remove obsolete top-level package wrappers

README.md

@@ -60,6 +60,9 @@ nix flake show --all-systems
 ├── README.md
 └── packages
     ├── common.nix
+    ├── scripts
+    │   ├── canonicalize-node-modules.ts
+    │   └── normalize-bun-binaries.ts
     ├── desktop
     │   ├── build-nix-desktop-package.mjs
     │   ├── default.nix
@@ -71,6 +74,7 @@ nix flake show --all-systems
 ## Notes
 
 - `packages/common.nix` contains the shared Bun workspace and `node-pty` setup used by both packages.
+- `packages/scripts/*.ts` contains the Bun install-tree normalization helpers used by `packages/common.nix`.
 - `packages/desktop/build-nix-desktop-package.mjs` is local packaging glue carried by this repo.
 - `packages/desktop/desktop-nix-autoupdate.patch` is a downstream patch for desktop auto-update messaging in package-managed installs.
 - Upstream source is pinned in `flake.lock` via the `t3code` input.