SSRF blocklist bypass: normalizeHost() misses dotted hex/octal IPv4, IPv4-compatible IPv6, and zone IDs

## Summary

\
ormalizeHost()\ in \packages/mcp-shared/src/endpoint.ts\ normalizes several non-standard IP representations before checking the blocklist, but misses dotted hex and dotted octal representations of private IP addresses.

## Affected Code

[\
ormalizeHost()\](https://github.com/cloudflare/cloudflare-os/blob/main/packages/mcp-shared/src/endpoint.ts#L35-L52) handles:
- ✅ IPv4-mapped IPv6: \[::ffff:7f00:1]\ → \127.0.0.1\
- ✅ Bare integer IPs: \

Start in packages/mcp-shared/src/endpoint.ts at normalizeHost(), referenced around lines 35–52. Review how the existing IPv4-mapped IPv6 and bare integer cases are handled, then cover dotted hexadecimal and octal IPv4 forms, IPv4-compatible IPv6, and zone IDs. Done means these non-standard representations cannot bypass private-IP blocklist checks.

Written by the indexing model from the issue text.