Re-package the aggregate: bundle Ward + ship the policing layer

Fold Ward into the single Institution install as its psychiatric-care
layer. package.sh now builds Ward clean and vendors Ward.dll plus its
defs and textures alongside the other layers, and the settings shim
gains a Ward (psychiatric care) checkbox that writes the shared
InstitutionSettings.ward flag.

Re-assembling also carries in Justice's now-shipping policing defs (the
constable work type and crime thoughts), so the aggregate finally
bundles colony crime and the weighed arrest as well. README updated to
five layers over one Core with policing shipped and Ward folded in;
adds the changelog, the Workshop preview, and the preview generator.

CHANGELOG.md

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+# Changelog
+
+Format: [Keep a Changelog](https://keepachangelog.com/en/1.1.0/). Versioning: [SemVer](https://semver.org/spec/v2.0.0.html).
+
+## [Unreleased]
+
+### Added
+- **Institution** — the aggregate mod. One install bundles the whole suite: the **Core** propensity /
+  record engine plus the **Contraband**, **Justice**, and **Gangs** feature layers, each behind its own
+  in-game toggle (all on by default). The layers remain modular — the suite can be split back into
+  separate mods at any time; this is packaging, not a merge.
+- **Settings panel** — a checkbox per layer:
+  - **Contraband** — concealment, search, escape tunnels.
+  - **Justice** — classification, deterrence, discipline & reform, parole, regime.
+  - **Gangs** — prison contraband economies and social capstone.
+  - **Policing** — colony crime and weighed arrests. A large behavioural change, so it carries its own
+    switch (on by default): your own colonists commit crimes on the propensity spectrum, and a weighed
+    arrest can end in a cell or a resisted breakout.
+
+  Toggling a layer off disables its systems in place, without uninstalling anything.
+
+### Notes
+- Requires **Harmony**. The suite's only Harmony-using code is Justice's prisoner-recreation postfix.
+- The standalone **Foul Play** framework bridges into this suite when both are installed.