Improve Traditional Chinese setup translations

[nrps9909]

Summary

• translate the remaining null ROCm backend label in zh-TW
• rewrite the first-run connection choices with natural Traditional Chinese terminology
• correct server status, GPU requirement, and model-description text shown during setup

Why

The current zh-TW locale mixes Mainland Chinese terms such as 插件, 創建, 通過, 網絡, 運行, 設置, and 文本 into the setup flow. A few strings also change the meaning: ComfyUI server is rendered as a service, and live painting is rendered as on-site painting. The ROCm backend label is null, so it falls back to English at runtime.

This patch keeps all English source keys intact, preserves the {link} placeholder, and limits changes to the visible setup and model-selection flow.

Validation

• parsed all 592 zh-TW keys against the generated language template
• confirmed 0 null values and matching runtime placeholders
• loaded zh-tw.json through Localization and rendered the {link} string
• pytest tests/test_settings.py tests/test_resources.py --ci: 18 passed
• pyright: 0 errors
• ruff format --check: 95 files already formatted
• ruff 0.15.20 check, matching the latest successful upstream CI run: passed

The full CI-style test suite on a fresh checkout reached 291 passed and 111 skipped; seven client tests require the separately installed test ComfyUI server described by their fixture. Ruff 0.16.2 also reports an unrelated pre-existing missing comma in ai_diffusion/backend/resources.py on the unchanged base branch.