Is she interested and I should make a move? Or she just polite?

I suck at taking hints, so I need a little help here. I've been vibing well with a girl at work. I'll keep it as short as possible.

Currently behaviour I've picked up, but unsure if she is just polite. It's a workspace after all.
- She asks questions of what I am up to on my free time and vacation. (polite?)
- She leans in closer to me when we talk (have a closer listen?)
- Our eye contact lingers a longer than normal.
- She jokes about I should tag along her vacation trip
- She gave me full attention even though another dude was talking to her. (my topic was more interesting)

Maybe it seems obvious, but to me everything can be politeness as well.
I've experienced colleagues doing the above, including being touchy. I made a move and apparently, she was just being friendly. Want to try doing the same mistake.

Is she interested and I should make a move? Or she just polite?
Is she interested and I should make a move? Or she just polite?
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