## Why
The unit tests stopped compiling after the `--pm` → `-p`/`-i` match-modifier refactor was left uncommitted, there was no RPM/completions distribution story, and invoking the tool without a TTY against an empty pipe silently returned nothing. This makes the project releasable and safe to run from agents/CI.
## Changes
- Make stdin handling robust: replace the fragile `!isTerminal` check with `stdinReader()`, which only reads node names when stdin is a real pipe/redirect carrying data. Terminals, `/dev/null`, and empty/closed pipes now fall through to a normal query, so running without a TTY behaves like an interactive run.
- Repair and expand `main_test.go` to match the current `buildQuery`/`run` signatures; add coverage for the match modifiers, all output modes, config precedence, and the new `stdinReader` logic. `httptest` stubs PuppetDB (no live deps).
- Add nfpm packaging (`packaging/nfpm.yaml`, `scripts/build-rpm.sh`): installs the binary to `/usr/bin/node-lookup` and bundles generated bash/zsh/fish completions under the standard system paths.
- Rework the Makefile to build into `dist/` and add `completions`/`rpm` targets.
- Split PR CI into `build`, `test`, and `pre-commit` workflows and extend `release` to build the RPM and `PUT` it to the artifactapi `rpm-internal` repo. Every step sets a `serviceAccount` and k8s resources.
The project directory has also been relocated under `prodenv`.
Reviewed-on: #13
Co-authored-by: Ben Vincent <ben@unkin.net>
Co-committed-by: Ben Vincent <ben@unkin.net>
