Fixes
- Legacy TLS fallback for SB8200 -- SB8200 modems with older firmware that only support TLS 1.0/1.1 now connect via a scoped legacy TLS retry before falling back to HTTP. Improved error messages include the original TLS error context (#184, #304)
Security
- Pygments 2.19.2 -> 2.20.0 -- Resolves CVE-2026-4539 (low severity, test-only dependency) (#305)