feat: add network.force_ipv4 config to fix IPv6 timeout issues (#8196)

On servers with broken or unreachable IPv6, Python's socket.getaddrinfo
returns AAAA records first. urllib/httpx/requests all try IPv6 connections
first and hang for the full TCP timeout before falling back to IPv4. This
affects web_extract, web_search, the OpenAI SDK, and all HTTP tools.

Adds network.force_ipv4 config option (default: false) that monkey-patches
socket.getaddrinfo to resolve as AF_INET when the caller didn't specify a
family. Falls back to full resolution if no A record exists, so pure-IPv6
hosts still work.

Applied early at all three entry points (CLI, gateway, cron scheduler)
before any HTTP clients are created.

Reported by user @29n — Chinese Ubuntu server with unreachable IPv6 causing
timeouts on lobste.rs and other IPv6-enabled sites while Google/GitHub
worked fine (IPv4-only resolution).

hermes_cli/config.py

@@ -706,6 +706,14 @@ DEFAULT_CONFIG = {
         "backup_count": 3,     # Number of rotated backup files to keep
     },
 
+    # Network settings — workarounds for connectivity issues.
+    "network": {
+        # Force IPv4 connections.  On servers with broken or unreachable IPv6,
+        # Python tries AAAA records first and hangs for the full TCP timeout
+        # before falling back to IPv4.  Set to true to skip IPv6 entirely.
+        "force_ipv4": False,
+    },
+
     # Config schema version - bump this when adding new required fields
     "_config_version": 16,
 }