refactor(packages): dissolve ui/ and rename sdk/ to scaffold/

git mv per the regrouping RFC: the five human-collaboration seams and
tui join packages/interaction/, app-boot becomes packages/boot/, and
jsonrpc joins the renamed scaffold/ (formerly sdk/) as its server half
beside client/protocol/create-sdk/helper/scripts/telemetry, whose
folders drop the legacy sdk- prefix. Three new group README triplets
replace the ui/ and sdk/ ones; tsconfig references/paths/globs,
knip keys, vitest globs, gate scripts, catalogs, docs, and the
lockfile follow. Adds the four settled FIXME rename markers
(dsh-sdk-server, dsh-sdk-telemetry, dsh-sdk-helper, dsh-sdk-scripts).

The scaffold folders diverge from their npm names until those renames
land, so tsconfig.base.json maps the three affected names explicitly
beside the group wildcard. Also repairs two pre-existing stale-path
classes the strengthened sweep surfaced: docs/web-styling.md's retired
web-ui host package and type-model spec fixture-literal joins.

app-boot's three Loader-composition specs time out at the default 5s
under full-suite parallel load on this filesystem (pre-existing;
pass isolated with --testTimeout=30000); interaction/scaffold/boot
suites otherwise green (687 passed).

packages/scaffold/helper/src/index.ts

@@ -0,0 +1,50 @@
+/**
+ * Shared domain and infrastructure for DeepSeek Harness SDK project tooling.
+ *
+ * FIXME: rename to `@deepseek-ai/dsh-sdk-helper` before the first tagged release —
+ * the current name is indefensibly generic as a published name
+ * ([regrouping Agent Note](../../../../.agents/notes/proposed/architecture/2026-07-29-package-regrouping.md)).
+ *
+ * @module @deepseek-ai/dsh-helper
+ */
+
+export { featureId } from './ids.ts'
+export { TextTemplate } from './templates/text-template.ts'
+export type {
+  FeatureSelection,
+  ProjectCreationRequest,
+  ProjectProfile,
+  RunInterface,
+} from './project/types.ts'
+export type { ChangeSet, ProjectCommitResult } from './project/change-set.ts'
+export { SdkProject } from './project/sdk-project.ts'
+export {
+  NodeCommandRunner,
+  NpmPackageManager,
+  createPackageManager,
+  inferPackageManagerName,
+  probePackageManagerVersion,
+} from './package-managers/package-manager.ts'
+export type {
+  CommandRunner,
+  PackageManager,
+  PackageManagerName,
+  PackageManagerVersionProbe,
+} from './package-managers/package-manager.ts'
+export { LocalPluginBlueprint } from './plugins/local-plugin-blueprint.ts'
+export type { LocalPluginKind } from './plugins/local-plugin-blueprint.ts'
+export type { Feature, FeatureInstallation } from './features/feature.ts'
+export type { FeatureRegistry } from './features/registry.ts'
+export { FeatureConfigurator } from './features/feature-configurator.ts'
+export { createBuiltinRegistry } from './features/builtin/index.ts'
+export { PromptCancelledError, requireAnswer } from './questions/prompt-port.ts'
+export type { NestedMultiSelectValue, PromptPort } from './questions/prompt-port.ts'
+export {
+  ConfirmQuestion,
+  SecretQuestion,
+  SelectQuestion,
+  TextQuestion,
+} from './questions/question.ts'
+export type { Question } from './questions/question.ts'
+export { ClackPromptPort } from './questions/clack-prompt-port.ts'
+export { HeadlessPromptError, HeadlessPromptPort } from './questions/headless-prompt-port.ts'