docs: fix incoming links to renamed/moved doc paths

Rewrites every markdown reference to the old paths:
- ARCHITECTURE.md → DESIGN.md
- docs/ARCHITECTURE.md → docs/CRYPTO.md
- FORMATS.md → docs/FORMATS.md

Touches CLAUDE.md (living-docs table + planning-references list),
per-crate ARCHITECTURE.md cross-refs, and any specs in
docs/superpowers/specs/ that referenced the old paths. Audit
history and test-run logs intentionally left untouched.

Spec: docs/superpowers/specs/2026-05-30-doc-structure-redesign-design.md

CHANGELOG.md

@@ -135,12 +135,12 @@ two confirmed bugs).
   the `.form-grid` cards above. Removes the visual rhythm break at the
   2-col → full-width transition. The popup surface is unchanged.
 - **Documentation refreshed for v0.5.0 (doc audit, 14 findings).**
-  `ARCHITECTURE.md` now describes four codebases (the
+  `DESIGN.md` now describes four codebases (the
   `relicario-server` pre-receive hook crate is no longer invisible);
   `CLAUDE.md` project tree and roadmap reflect current state;
   `docs/SECURITY.md` names the server crate and its `verify-commit` /
   `generate-hook` subcommands and notes the without-the-hook-it's-
-  advisory caveat; `docs/ARCHITECTURE.md` shows `settings.enc` as a
+  advisory caveat; `docs/CRYPTO.md` shows `settings.enc` as a
   parallel artifact in the vault-creation flow; the foundational
   design spec gains a "historical" status banner pointing readers at
   the current docs.