fix!: make network inspect Docker-compatible

[jahirvidrio]

What problem does this solve?

mocker network inspect <name> and mocker inspect --type=network <name> emit mocker's internal NetworkInfo shape — a single lowercase JSON object via TableFormatter.printJSON, not the Docker network.Inspect array of objects with PascalCase keys and nested IPAM. Scripts that pipe to jq and expect Docker fields (.IPAM.Config[0].Subnet, .Containers, top-level array) break.

mocker inspect --type=network <name> is also rejected at parse time today: the InspectObjectType enum only knows image | container, so the route is silently absent. Same for the auto-fallback path — mocker inspect <name> never tries network even when the target exists as a network.

This closes the last shipped command in the Docker-parity gap after #25 (image inspect) and #40 (container inspect).

What changed

• New NetworkInspect DTO + pure mapToNetworkInspect mapper in Sources/MockerKit/Models/NetworkInspect.swift, mirroring the image- and container-inspect pattern. NetworkIPAM conforms to Encodable only with a custom encode(to:) that calls encodeNil(forKey: .Options) — Docker emits literal "Options": null for an unset IPAM driver-options map, not {}, and the default Swift Codable would have emitted {}.
• New inspectNetworks collector in Sources/MockerKit/Models/InspectOperations.swift with accumulate-then-fail multi-arg semantics: unknown targets emit Error response from daemon: network <name> not found to stderr, processing continues, exit 1 at the end. This intentionally diverges from inspectContainers (which throws on first miss) — copying that pattern would break multi-arg parity with docker network inspect a b c.
• Sources/Mocker/Commands/Network.swift: rewired NetworkInspect to variadic names: [String], removed the --verbose flag (was a no-op), and migrated output from TableFormatter.printJSON to InspectFormat.emitArray so the subcommand emits a Docker-shaped JSON array with unescaped slashes and honors --format / --format json the same way image and container inspect already do.
• Sources/Mocker/Commands/Inspect.swift: extended InspectObjectType with .network, added the .network branch in run(), and added network as a third attempt in the auto-fallback loop after containers and images so mocker inspect <name> resolves to a network when neither matches.
• Containers map ships as {} empty for v0.6.0. Apple-runtime enrichment (real EndpointID / MacAddress / IPv4Address from container network inspect <id>) is intentionally deferred to a non-breaking follow-up so the breaking-shape change lands within the review budget. Fabricating Name-only stub entries was considered and rejected: Docker never emits entries with empty runtime-field strings, so doing so would invent a shape Docker would never produce.

Breaking change

mocker network inspect no longer emits the lowercase NetworkInfo object. Scripts that read .subnet, .gateway, or .containers from a top-level object must migrate to .IPAM.Config[0].Subnet, .IPAM.Config[0].Gateway, and .Containers (a map, empty {} in v0.6.0 until the enrichment follow-up). The top-level is now a JSON array, so jq filters need .[0].Name instead of .name. mocker inspect --type=network <id> is a new route — it did not exist before — so nothing breaks there. Multi-arg network inspect a b c now returns one combined array (previously rejected: single-arg only).