refactor: who-pays paper voice — first-person consistent, remove "we argue"
Changed abstract to first-person voice: "I cross-reference" instead of "We", replaced "we find that" with direct bullet-style statements for punchier prose. Removed "We argue that" in favor of direct assertion. Applied VOICE.md guidelines: short sentences, personal conviction, no hedging language.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>