v1.2.0

No command, flag, exit code, or JSON field changed in this release: the
capability catalogue is byte-identical to v1.1.0. What changed is the shape of
the source tree behind it, and — for anyone using the crate as a library — the
type of every error it can return.

Changed

• The single crate is now a 24-package Cargo workspace: six paredit-core-*
  packages (syntax, semantics, edit, lint-engine, workspace, cli) and eighteen
  paredit-feature-* packages, with the binary as a thin composition root.
  The paredit_cli façade re-exports every package module, so existing import
  paths such as paredit_cli::domain::sexpr still resolve.
• The lint engine no longer depends on the rule registry. Rules are supplied
  through a RuleCatalog, which breaks the cycle that previously forced the
  engine and the 134 rules into one compilation unit.
• Breaking for library consumers. Fallible entry points return typed error
  enums instead of anyhow::Result — SexprError, EditRefusal, LintError,
  CliError, and per-feature equivalents. A caller that names a return type or
  matches on an error must be updated; ? into an anyhow::Result still
  compiles unchanged. The CLI's own stderr text is unchanged, because main
  still converts at the boundary.
• Several types now make invalid states unrepresentable rather than checking
  for them: inline-function's call selection, split-file's destination, and the
  refactor manifest's hash and flag comparisons, which are derived rather than
  stored.
• The compatibility guide no longer lists the Rust library API as a stable
  surface. The crate is publish = false with no registry release, and the
  supported interface is the command line — see
  Releases and compatibility.