Add compiler/builder/prompt_builder.py: build_prompts(category_map, config,
logger=None) -> CompilerResult (data = tuple[PromptOutput]), per MASTER_SPEC §19.
- Emits one output per canonical category (in order) plus reserved `negative`
and `scene`; V1 always emits all 21 outputs for stable node sockets.
- Tags joined with config.prompt_builder.separator (default comma, no surrounding
whitespace, no trailing separator). Empty categories yield an empty string,
never null/placeholder (§19.4).
- Formatting only: no tag generation, removal, reordering, dedup, or escaping
(§19.1, §19.5). Output names are the lowercase canonical category ids and
`negative`/`scene`, mapping to the §19.2/§19.3 display names.
Tests: output set (19 + 2 reserved), comma join, order preservation, empty
strings, reserved-empty, custom separator, no-trailing-separator, no escaping,
determinism.
Co-authored-by: kunail0804 <kunail0804@gmail.com>
Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>
