chore(repo): add git-cliff config, sort deps, add rust-version

- Add cliff.toml with GitHub remote wiring, issue link parsers, and
  clean group names (no sort prefixes)
- Add rust-version = "1.87.0" and codegen-units = 1 to workspace
- Sort workspace.dependencies alphabetically; add notstrap path entry
- Add CLAUDE.md preflight block; reformat workspace table to 100-col
- Delete stale brainstorm artifacts and root HANDOFF.md

.ctx/HANDOFF.md

@@ -1,4 +1,4 @@
-# Handoff — notfiles (2026-07-07)
+# Handoff — notfiles (2026-07-14)
 
 **Branch:** main | **Build:** unknown | **Tests:** unknown
 
@@ -11,6 +11,7 @@
 ## Log
 
 - 20260606.135918: done=13 running=0 pending=0 blocked=0
+- 2026-07-08: hexagonal architecture refactor with adapters and integration tests, notsecrets cleanup, config payload moved to notfiles-config repo
 - 2026-04-17: Added notnet crate with YubikeySource and threaded Tailscale into notstrap; design spec complete
 - 2026-04-15: Hardened bootstrap and hook-state failure handling, made notfiles FileStore usage real, and fixed copy-drift safety coverage
 - 2026-04-15: Pruned completed items from handoff; GitHub issues plus doob are now the source of truth for active work