refactor: Golf Quantum info with fable

[jstoobysmith]

Golfing Quantum Info with Claude Fable. Prompt (adapted from @Vilin97's). Not asking for this to be reviewed or merged yet.

Golf AS MUCH AS POSSIBLE in just Quantum Info. 
Do not change statements, and do not cram tactics on one line. Genuinely make proofs
shorter and simpler by streamlining arguments, increasing mathlib usage, reduce code duplication, increase code reuse, use more powerful tactics, etc. Do not change any statements and definitions - only work on proofs! Be thorough, go project by project carefully. If spawning agents, use max reasoning, and tell them to be very
thorough. DO NOT ASK ME ANYTHING AND DO NOT GIVE UP, KEEP FINDING NEW WAYS TO COMPRESS.

[github-actions]

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