fix: closure checking apostrophe confusingly named is_tack

[hippietrail]

Issues

N/A

Description

I was going to work on some more mixups between "tack" and "tact" but while grepping for existing logic doing this I happened across a closure named is_tack() inside lex_word() in lexing/mod.rs Apparently this came about in one of the commits that made up the Weir PR: 46f4547

The closure actually checks for presence of an apostrophe. I'm guessing this was a typo for "tick" given that ` is often called "backtick" though Googling for whether anyone also calls ' "tick" I couldn't find any evidence of that. So I've just changed it to the most vanilla / least confusing name is_apostrophe()

The only benefit of this bikeshedding change is that it won't be a red herring again for anyone else working on "tact" vs "tack" in the future (-:

Demo

N/A

How Has This Been Tested?

cargo test

AI Disclosure

• I am a human and didn't use any AI.
• I used LLM features of my editor, but not an agent.
• I used an AI agent interactively.
• I am an agent or I got an agent to do the work autonomously.

Checklist

• I have performed a self-review of my own code
• I have added tests to cover my changes
• I have considered splitting this into smaller pull requests.