docs(presets): refocus constitution-sync README on what it restores

Reframe the intro around what the preset restores and what the user opts
into, rather than describing current Spec Kit default behavior. Be honest
that propagation was removed deliberately (duplicates the source of truth,
fights composition) and this preset knowingly reintroduces it and its
tradeoffs. Minor flow fixes (comma splice, terse bullet).

Assisted-by: GitHub Copilot (model: Claude Opus 4.8, supervised)
Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>
Copilot-Session: afa7c1d2-147b-4f62-a6fc-a2cc824cfa3e

Author: mnriem

presets/constitution-sync/README.md

@@ -1,16 +1,30 @@
 # Constitution Template Sync
 
-An **opt-in** preset that makes `/constitution` propagate amended guidance into your project's own
-templates and command files. After you update the constitution, it aligns
+An **opt-in** preset that restores `/constitution`'s ability to propagate amended guidance into your
+project's own templates and command files. After you update the constitution, it aligns
 `plan-template.md`, `spec-template.md`, `tasks-template.md`, project-local command files, and
 guidance docs so they reflect the current principles.
 
-The current version of Spec Kit does **not** do this by default. Its default model is
-**runtime resolution**: `plan`, `tasks`, and `analyze` read `.specify/memory/constitution.md` live
-on every run, so templates carry a pointer (`[Gates determined based on constitution file]`) rather
-than a frozen copy. Add this preset only if you specifically want the guidance materialized into
-reviewed, committed artifacts — and read the [caveats](#caveats-you-take-on) first, because
-propagation and the preset composition stack pull in opposite directions.
+This propagation used to be built into `/constitution`; it was dropped when the command moved to the
+preset model. Installing this preset opts you back into it: you get the guidance materialized into
+reviewed, committed artifacts instead of relying on runtime resolution alone.
+
+> **What you're opting into.** Propagation was removed deliberately — it duplicates the constitution
+> as the source of truth and can fight the composition stack (materialized edits get shadowed or
+> clobbered on the next recompose). This preset knowingly **reintroduces** that behavior, and those
+> tradeoffs, for teams that want it. Read the [caveats](#caveats-you-take-on) before installing.
+
+For most projects the default composable stack is the **recommended** approach, and at organization
+scale it is usually the stronger governance model. Runtime resolution keeps the live constitution as
+the single source of truth (nothing to re-sync, so nothing drifts), and the stack composes the
+**entire** Spec Kit ecosystem — not just the SDD commands, but every command, template, script and
+extension — with explicit priority levels, strategies, and independent versioning. It is a
+capability, not automatic governance: a core team authors its own organizational presets and
+extensions, then owns, versions, and audits that policy in one place and rolls it across many
+repositories, instead of scattering frozen, per-repo copies no central team can see. This preset is
+a supported escape hatch for teams whose workflow depends on reviewing materialized artifacts
+directly — useful as a bridge, though for org-wide policy the better long-term path is usually a
+versioned preset a core team maintains.
 
 ## What it does
 
@@ -19,15 +33,15 @@ current core command (via `{CORE_TEMPLATE}`), so it stays forward-compatible wit
 appends a propagation pass that, after the constitution is written:
 
 - Aligns `plan/spec/tasks-template.md` in `.specify/templates/` with the updated principles.
-- Updates **project-local** command files and guidance docs for stale references.
+- Updates **project-local** command files and guidance docs to correct stale references.
 - Extends the Sync Impact Report in `.specify/memory/constitution.md` with the files it touched.
 
 ## What it does not do
 
 - It does **not** change behavior for anyone who does not install it — the default runtime
   resolution model is untouched.
 - It does **not** disable runtime resolution. `plan`, `tasks`, and `analyze` still read the live
-  constitution every run; this preset adds materialized copies on top, it does not replace the
+  constitution every run; this preset adds materialized copies on top — it does not replace the
   source of truth.
 - It does **not** edit versioned, package-owned files — templates or command files provided or
   wrapped by another preset or extension. Those are recomposed from the resolution stack, so it