BrandDocs v0.2.0

Hardening release: correctness fixes across all three formats, a real
doctor preflight gate, a uniform destructive-action policy, and a
3.10+ / CI matrix toolchain. Brand Profiles from 0.1.0 keep working
unchanged (schema 1.x is read as-is).

Added

• doctor is now a preflight gate, not just a report: it exits nonzero
  when a required Python dependency is missing, so a broken environment
  fails before generation instead of mid-run.
• doctor --json prints the machine-readable dependency/renderer probe;
  doctor --fast skips the slow LibreOffice render probes (visual QA is
  marked "not probed") for a quick check.
• PowerPoint now expands reusable components / sections fragments,
  matching the Word vertical: a profile-defined fragment inlines
  identically across formats, fail-closed (an undefined reference raises
  rather than silently dropping content).
• Schema: a profile whose major version is newer than this build supports
  now fails with a single clear "upgrade brand-docs or re-extract" message
  instead of a pile of confusing per-field errors, and a forward
  migrate() seam is in place for future schema growth.

Changed

• The destructive-action confidence floor (>= 0.5) is now applied
  uniformly at every reconcile site across Word, PowerPoint, and Excel
  from a single source of truth, so a low-confidence delete is downgraded
  to keep-with-warning consistently (previously only some sites enforced
  it).
• PowerPoint now honors the profile-resolved body placeholder index
  (ph_idx) when filling body content, instead of always assuming the
  first placeholder.
• Python floor is now 3.10+ (declared in pyproject.toml
requires-python). CI runs a 3.10 / 3.11 / 3.12 matrix, a ruff lint +
  format gate, and a real-render lane that installs LibreOffice + poppler
  and actually executes the visual end-to-end tests (a broken renderer
  fails the lane).
• Reference docs (block catalog, profile schema) are synced to the engine
  and guarded by a freshness test; a fixture-determinism guard keeps the
  test fixtures byte-stable.
• Internal: a shared ooxml/ layer now centralizes qualified-name
  helpers, the complex-field walk, and ZIP byte-idempotency, removing
  duplicated boilerplate from the format generators.
• README slimmed and repositioned; the GitHub Pages site is split from the
  human-facing documentation/; em dashes removed across skills and
  metadata.

Fixed

• Excel no longer crashes when a named region's first row straddles a
  merged banner: writes to a merged-slave cell are guarded (only the merge
  anchor is writable) and the skipped value surfaces as a block_degraded
  warning instead of raising or being lost.
• PowerPoint no longer silently drops Component / Section / Toc / Divider
  blocks it has no native writer for: each now emits a visible
  block_degraded warning, honoring the "never drop content silently"
  invariant.
• Word generation is now byte-deterministic: re-running the generator on
  the same inputs produces an identical file (ZIP entry timestamps are
  pinned), matching the existing PowerPoint and Excel behavior.