Rumor Scanner — AIsa Edition Scan for early market signals and rumors using the AIsa API. Usage Arguments - : Filter by (default), (M&A), , , or - : Append structured JSON summary Signal Categories - M&A / Takeover Signals : Acquisition, merger, buyout, strategic review keywords - Insider Trading Activity : SEC EDGAR Form 4, cluster buying, 10b5-1 deviations - Analyst Actions : Upgrades, downgrades, price target changes 15%, double-upgrades - Social & News Whispers : "hearing that", "sources say", "rumored to", unusual social spikes - Regulatory / SEC Activity : 13D/13G filings, investigation…