fix: filter ports by network_id for floating IP attachment

[Koan-Bot]

What

add_floating_ip_to_server() now filters ports by network_id instead of blindly picking the first port.

Why

On multi-homed VMs (multiple NICs on different networks), the old code grabbed ports->[0] — whichever port the API returned first. This could attach the floating IP to the wrong interface (e.g. a management NIC instead of the production one). The original code even had a comment acknowledging this: # pick the first port for now (maybe need to check the network_id...).

How

• Added optional network_id parameter to add_floating_ip_to_server() via %opts hash
• When provided, filters the server's ports to find the one on the specified network
• create_vm() now passes $network->{id} (the VM's internal network) to ensure correct port selection
• Omitting network_id preserves backward-compatible first-port behavior

Testing

• New test file t/floating-ip-port-filter.t with 3 scenarios:
  • Multi-homed VM: correct port selected by network_id
  • No matching port: dies with descriptive error
  • No network_id: backward-compatible first-port fallback
• Full suite passes (7 files, 27 tests)

🤖 Generated with Claude Code

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Quality Report

Changes: 4 files changed, 191 insertions(+), 6 deletions(-)

Code scan: clean

Tests: passed (OK)

Branch hygiene: clean

Generated by Kōan post-mission quality pipeline