chore: bump every port to 1.6.1

[JeanExtreme002]

Moves the three declared versions to 1.6.1, which is what a release of that
number needs: verify-versions refuses to publish anything unless Python,
Node.js and Go all declare the same one.

file	field
python/FlightRadarAPI/__init__.py	__version__
nodejs/package.json	version
nodejs/package-lock.json	version (both entries)
go/flightradarapi/doc.go	Version

The Node side was bumped with npm version --no-git-tag-version, so the lock
file moves with the manifest — npm ci, which the workflow runs, fails on a
lock that disagrees with it. The fastq: ^1.6.0 dependency further down that
file is untouched.

Checked

The same three extractions the release gate performs:

python=1.6.1 | npm=1.6.1 | go=1.6.1   → verify-versions would pass
npm ci                                 → accepted the lock file
go test ./flightradarapi               → ok
import FlightRadarAPI                  → 1.6.1, client instantiates

After merging

Publishing the v1.6.1 release runs the whole chain: PyPI, npm, and then the
go/v1.6.1 tag, which the Go toolchain needs because the module lives in a
subdirectory. Nothing to tag by hand this time.