Release v4.197.0

Changed

• ui profile gains root template [blueprint <Blueprint>] <Name> [version "<range>"] with option <name> <value> lines, an appearance block (color scheme light|dark|system, accent "<#hex>") and new screens use template <ref>. layout <Name> stays readable beside it.
• New syntax nodes RootTemplateSyntax, ShellOptionSyntax, ProfileAppearanceSyntax, NewScreenTemplateSyntax; parser (ProfileShellParser), printer (byte-identical round trip), walker, transport schema (C# and TS generated files), docs (grammar, ui-profile, templates, diagnostics), Monaco completion/keyword docs, VS Code TextMate grammar, Invoicing sample.
• Diagnostics PLAY0788 (malformed/repeated shell lines), PLAY0789 (malformed/repeated appearance), PLAY0798 (second root template); a bad version range reuses PLAY0721.
• Template renames stay refused (layouts/templates are not rename targets), so a profile's reference cannot go stale; folder merge needs no change (a profile lives in one file).

Fixed

• Part of #825; epic Cratis/Scene#157. Validator checks against Scene (template/option existence) follow with #826.