[tool] reading_time (#163)

[PurpleSwtr]

Summary

Adds the reading_time tool requested in #163.

Behavior

I implemented two ways to send text. (If this isn't suitable, I can easily fix it and remove this functionality.)

But I thought it would be convenient to also be able to send a file path to the tool, rather than, for example, pasting 5,000+ lines of text into the terminal.
It uses the standard Python method of redirecting input file using the "<" operator on the command line.

Examples

I used rounding by adding half the divisor.

(90 words): (90 + 100) // 200 -> 190 // 200 = 0 (rounded down, since it's less than half).
(110 words): (110 + 100) // 200 -> 210 // 200 = 1 (rounded up, since it's over the threshold).
(290 words): (290 + 100) // 200 -> 390 // 200 = 1 (rounded down, closer to 1).
(310 words): (310 + 100) // 200 -> 410 // 200 = 2 (rounded up, closer to 2).

• python bitbox.py reading_time "text, < 100 words" -> 0
• python bitbox.py reading_time "text, = 100 words" -> 1
• python bitbox.py reading_time "text, = 200 words" -> 1
• python bitbox.py reading_time "text, = 400 words" -> 2

and also i tested this on some files, this is the second way to use:

• python bitbox.py reading_time < "README.md" -> 2 (397 words) p.s. file of this project
• python bitbox.py reading_time < "1.md" -> 5 (959 words)
• python bitbox.py reading_time < "2.md" -> 22 (4469 words)

Checklist

• File is in tools/ directory
• File has header comments (# tool, # description, # author, # example)
• File has a run() function that returns a string
• Uses stdlib only (no external dependencies)
• Tested locally with python bitbox.py <tool_name> <args>

Closes #163