fix: avoid panic on nil container Config/NetworkSettings/HostConfig

[JamBalaya56562]

getContainers dereferenced container.Config, container.NetworkSettings and container.HostConfig (and GetContainerAddresses/renderAddress dereferenced NetworkSettings/Config) without nil checks. Inspect can return these as nil for some containers/daemons, causing a panic that aborts generation for every container.

This copies each pointer into a zero value when nil, so the container is still emitted with its ID/Name and empty fields instead of crashing, and makes GetContainerAddresses nil-safe (it's exported and used elsewhere). State is a value (not a pointer) and ranging nil maps/slices is safe, so those are left unchanged.

Adds nil-struct tests for GetContainerAddresses and getContainers.

Fixes #227

🤖 Generated with Claude Code

[Copilot]

Pull request overview

This PR hardens container inspection and address rendering against nil docker.Container sub-struct pointers returned by some Docker daemons/remote APIs, preventing panics that would otherwise abort template generation for all containers.

Changes:

• In getContainers, copy Config, NetworkSettings, and HostConfig into zero-value locals when their pointers are nil, and use the locals for field access.
• Make context.GetContainerAddresses / renderAddress tolerant of nil NetworkSettings (and nil Config for the exposed-ports fallback).
• Add tests covering nil struct pointers for both getContainers and GetContainerAddresses.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
internal/generator/generator.go	Avoid nil-pointer dereferences during container inspect processing by using zero-value copies.
internal/generator/generator_test.go	Add regression test ensuring nil Config/NetworkSettings/HostConfig doesn’t panic during getContainers.
internal/context/address.go	Make address rendering and port enumeration nil-safe for missing NetworkSettings/Config.
internal/context/address_test.go	Add tests ensuring GetContainerAddresses returns empty (and doesn’t panic) when struct pointers are nil.

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[JamBalaya56562]

Addressed Copilot's review feedback — renamed the shadowing config local to containerConfig and fixed the adresses → addresses typo.