Add --no-shuffle and --no-limit flags

[ptrsauer]

Description

Two new CLI flags for more control over test content:

--no-shuffle: Don't shuffle the word order. Useful when practicing from a specific ordered list (e.g., frequency-ranked words) or for reproducible tests.

--no-limit: Override the word count limit (-w). Use the entire word list instead of sampling. Useful for exhaustive practice of a language file.

Source

• Fork: SimonRenblad/ttyper (8 commits ahead)
• Scope: Small changes in src/main.rs (CLI args + content generation logic)
• Complexity: small

Design notes

• --no-shuffle should work with both built-in languages and custom files
• --no-limit should be mutually exclusive with -w (or override it with a warning)