[docs] docs: sync documentation with recent code changes

[github-actions]

Documentation Sync - Feb 1-7, 2026

This PR synchronizes documentation with code changes from the past 7 days.

Changes Made

1. Updated docs/environment.md:

   • Removed HTTP_PROXY and HTTPS_PROXY from internal environment variables table
   • Updated "Default Behavior" section to reflect transparent iptables-based proxying
   • Added proxy variables to excluded variables list with explanation
   • Added historical note about removal in v0.13.5

2. Updated docs/chroot-mode.md:

   • Documented procfs mounting for Java and .NET runtime support (v0.13.13)
   • Updated execution flow diagram to include procfs mount step
   • Added new "Procfs Mounting for Java and .NET" section explaining why it's needed
   • Updated capability management table to include CAP_SYS_ADMIN
   • Removed /proc/self from volume mounts table (replaced with fresh procfs mount)

3. Updated docs/usage.md:

   • Updated host access security warning to reflect port restrictions (v0.13.13+)
   • Added explanation that access is limited to ports 80, 443, and --allow-host-ports
   • Updated MCP gateway example to show --allow-host-ports usage
   • Added note about default allowed ports

4. Fixed AGENTS.md:

   • Corrected documentation file reference from non-existent LOGGING.md to docs/logging_quickref.md
   • Added reference to docs/environment.md

Code Changes Referenced

• Commit 54fd26e (v0.13.5): Removed HTTP_PROXY/HTTPS_PROXY env vars from agent container
• Commit dda7c67 (v0.13.13): Mount procfs in chroot for Java/dotnet runtime support
• Commit 12683ac (latest): Restrict host gateway iptables bypass to allowed ports only

Verification

• ✅ Documentation changes match actual code behavior
• ✅ Examples tested for accuracy
• ✅ Consistent with existing documentation style
• ✅ Version numbers and commit references verified

Impact

These updates ensure users have accurate information about:

• How environment variables are handled (no more confusion about HTTP_PROXY)
• Java/.NET support in chroot mode (eliminates "Cannot execute dotnet when renamed to bash" errors)
• Security improvements in host access mode (port restrictions)

AI generated by Documentation Maintainer