Changed 'When NOT to Use' section to avoid implying Tailscale is
'safer' than identity-aware proxies like Pomerium.
Pomerium is a security-focused identity-aware proxy - it's not less
safe than Tailscale, just a different approach (multi-user vs personal).
Updated to focus on actual inappropriate use cases:
- No authentication (TLS terminator only)
- Bypass paths exist
- Header handling uncertain
- Single-user scenarios (where Tailscale may be simpler, not safer)
cd77ee076f