3e3615e2c8
Add per-project configuration via .claude/last30days.env, discovered by walking up from cwd. Uses the same .env format as the existing global config — no new parsers or formats. Priority (highest wins): 1. Environment variables 2. .claude/last30days.env (per-project) 3. ~/.config/last30days/.env (global) Also adds file permission checking — warns to stderr if config files are readable by other users (should be chmod 600). Includes tests for discovery, precedence, source tracking, and permission warnings. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>