fix: add OpenEnv root reset and step aliases

fix: improve model router error handling and add debug logging

test: verify strict output contracts on 200-case matrix

test: validate 35 non-template existing domains across output types

test: run 6100-case template and non-template stress matrix

fix: GitHub trending CSV output returns correct columns

fix: resolve bare-domain assets to direct URLs

test: add full site template matrix coverage

fix: resolve scraper functionality and plugin issues

test: add comprehensive API and core module tests

feat: add modular plugin system for extensions

feat: add client API key configuration and model selection

test: add comprehensive backend test suite