feat(development): add indexed package search CLI

- Install nix-search-cli on every host
- Document fast stable-channel searches and pinned-package searches

README.md

@@ -103,6 +103,17 @@ language runtimes or Kubernetes/Terraform tooling. Android
 Studio remains on the ThinkPads as an existing IDE/workflow choice, but its
 bundled SDK is worth reviewing if moving fully to project-local tooling.
 
+For fast package discovery, the shared tools include `nix-search-cli`:
+
+```sh
+nix-search --channel=26.05 blender
+```
+
+This queries the online search.nixos.org index rather than evaluating nixpkgs
+locally. Results reflect the current stable channel index, which can be newer
+than this repository's lock file. To search the exact pinned package set, use
+`nix search --inputs-from /path/to/nixos-config nixpkgs blender` (slower).
+
 ## Migration and package review
 
 The original repositories are left untouched. No credentials were found in the