Add compiler/splitter/category_splitter.py: split_into_categories(tags,
logger=None) -> CompilerResult (data = CategoryMap), per MASTER_SPEC §18.
- Each Resolved Tag is placed in the category recorded on it by the Resolver
(its Knowledge Base Entry category); tags are never modified, generated, or
removed (original objects kept verbatim).
- Tags within a category preserve Resolver order; category ordering follows the
shared canonical 19-category order; empty categories are omitted (§18.4).
- Defensive: a tag whose category is outside the 19 stops with SC0008.
Tests: assignment, within-category ordering, canonical category ordering,
empty-category omission, tag identity preserved, empty input, and SC0008.
Co-authored-by: kunail0804 <kunail0804@gmail.com>
Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>
