[ronaldtse]

docs: the doctrine concept pages

Track 06 asks for a concept page per doctrine ruling. The existing set
covers the model (anatomy, metaschema, components, algebra, relations)
and the URN mapping; the rulings that shape parsing and rendering were
only in the library notes. Add five prose-only pages:

• Lossless Faces — a printed spelling is identity-bearing; aliases
  converge in recorded rounds; a canonical that cannot re-parse is a
  counted quarantine, not a silent re-spelling.
• Dual Perspectives — ISO/IEEE vs IEEE/ISO (and ISO|IDF vs IDF|ISO)
  are peer assignments; no canonical form, no hints, no routing.
• The D= Designator — P marks the project, D= carries the stage, the
  iteration glues, the year joins in IEEE format; DDIS is an alias.
• Stage Words — the draft word is "Draft" alone; project-stage drafts
  suppress the type word; stage words and D= are faces of one stage.
• The Corpus Contract — cases, schema, provenance, ledger, quarantine
  and the three-layer rhythm with a receipt at every step.

Registered in both conceptOrder and the sidebar. No code blocks or
method signatures; identifier notation stays inline, per the concept vs
API split.

Verified: npm test 380/380; npm run check 0 errors, 0 warnings.