Deep category now uses gpt-5.4 as its default model across all providers
(openai, github-copilot, venice, opencode), matching Hephaestus's GPT 5.4
upgrade. The requiresModel constraint is removed since gpt-5.4 is widely
available. Adds openai/gpt-5.3-codex -> openai/gpt-5.4 config migration
for existing user configs. Deep category prompt optimized for GPT 5.4's
stronger native capabilities (leaner, less verbose).
Fixes#1804, fixes#1962
The migration entry 'gpt-5.2-codex → gpt-5.3-codex' caused the plugin to silently overwrite user configs on every startup with a model that doesn't exist in the OpenAI API. Users explicitly setting gpt-5.2-codex (the correct current model) were forced to revert their config manually every session.
YeonGyu-Kim