SEC: fix 8 bugs from security audit (CRIT + HIGH + MED + LOW)

SEC: mask API keys and channel tokens in settings API

AUDIT: comprehensive security bug report (40 findings)

SKILLS: rewrite all 4 skills to Anthropic SKILL.md standard

FEAT: /summary command for TG bot — conversation summarization

README: add support/star line at the top

PERF: browser_go and browser_click now return full page content

MEMORY: persistent chat history in SQLite + thorough testing prompt

FIX: add browser automation tools to skill .md files + debug logging

FIX: inject skill safetyRules into TG/DC/SL poller system prompts

BROWSER-AUTO: Playwright browser automation tools

TOOL: open_url — opens URL in local browser (Win/Mac/Linux)

FIX: force bot to reply in user's language, not fetched content language

FIX: 7 critical bugs in channel polling (TG/DC/SL)

FIX: save channels/baseUrl to DB, add channelId fields for Discord/Slack