IOC quality pass
Structural fixes for false positives across every IOC type:
- Quote attribution — IOCs from quoted tweets now point to the original author, not the quoter.
- Hash filter — hex strings inside URL paths or subdomains (cloud bucket IDs, webinar IDs, phishing-kit session IDs) no longer leak as MD5/SHA256.
- Research-host whitelist — links to sample-sharing services no longer emit as URL or domain IOCs.
- CDN IPs — Anycast edges filtered; the domain is the actionable IOC, not the CDN frontend.
~10K historical false-positive rows cleaned.