Enable servers to define reusable prompt templates that VS Code can surface as prompt files and slash commands, standardizing common AI tasks.

cc @legomushroom

Ideas to explore:

• Share entry points with Prompt files
• Slash command surfaces (e.g. /commit)
• Argument input forms
• Preview before execution

Template system to explore:

• Dynamic arguments with validation (required/optional)
• Resource context injection (files/APIs/databases)
• Multi-step interaction chaining