brainless 0.7.0

Take a bad source back out, one document per source, concepts decided in Buzz, and
frontmatter that Obsidian can read.

• Retract a source. tools/retract_source.py traces a source that turned out wrong:
  its summaries (raw twin and book folder included), the concept pages that cite it, the
  pages that link to it. With --apply --reason "..." it goes into
  _Agent-Context/retracted.md and the compiler never compiles it again. A concept claim
  that stood on it alone is struck and kept in Superseded, marked retracted with the
  reason; a claim with other sources keeps them. The validator lets only the retracted
  links go, and a page it refuses stays as it was and is named for a hand edit.
• One document, one source. A raw conversion beside its cleaned file, and a reading
  sheet beside a book summary, stop compiling as separate sources. Their old summaries go
  to .wiki/_archive/summaries/ with the reason in LOG.md, and links move to the copy
  that stays. Concepts read one summary per document.
• Concepts are decided in Buzz. tools/concept_review.py posts each concept proposal
  to #dreaming; reply evet, hayır or atla. The Sunday proposal pass reads the whole
  catalogue and stops while five proposals wait.
• Contradiction check. tools/contradiction_check.py reads each night's new summaries
  against their nearest pages and writes real conflicts to
  _Agent-Context/CONTRADICTIONS.md and the change brief. No page is edited.
• Run log fix. The run log dropped any line with a digit in a key, so a night of
  failed calls could read as ok. Fixed, and a partial run now warns in health.
• Quoted frontmatter. A colon followed by a space in a title or summary made the whole
  frontmatter block invalid YAML, and Obsidian dropped the page's properties. The tools
  never noticed because they read values by regex. tools/file_query.py and the idea
  writer now quote a value when it needs quotes (concepts.yaml_scalar), and every page
  the model writes passes through concepts.quote_frontmatter before it lands: summaries,
  projects, digests and concept pages. Lists, block scalars and quoted values stay as they
  are, and a second pass changes nothing. A # inside a summary, which YAML reads as a
  comment and cuts off, is quoted too.
• Readers strip the quotes. concepts.fm_value and lint_wiki.parse_fm return the
  value without its quotes, so search, the index and the graph export see the same text as
  before.
• Repair existing pages once, from the vault root:
  python3 -c "import sys;sys.path.insert(0,'tools');import concepts as C;from pathlib import Path;[p.write_text(n) for p in Path('.wiki').rglob('*.md') if (n:=C.quote_frontmatter(t:=p.read_text()))!=t]"
• Test: tools/tests/test_file_query.py.