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

crates/notcore/Cargo.toml

@@ -10,7 +10,6 @@ categories.workspace = true
 description = "Shared types and config for the notfiles dotfiles manager"
 
 [dependencies]
-anyhow    = { workspace = true }
 dirs      = { workspace = true }
 serde     = { workspace = true }
 strsim    = { workspace = true }