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/project/change-set.ts

@@ -0,0 +1,26 @@
+/**
+ * Result summary for one SDK project edit session.
+ *
+ * @module @deepseek-ai/dsh-helper/project/change-set
+ */
+
+import type { FeatureId } from '../ids.ts'
+
+/** Immutable description of committed or pending project changes. */
+export interface ChangeSet {
+  addedFeatures: readonly FeatureId[]
+  enabledFeatures: readonly FeatureId[]
+  disabledFeatures: readonly FeatureId[]
+  configuredFeatures: readonly FeatureId[]
+  addedPlugins: readonly string[]
+  enabledPlugins: readonly string[]
+  disabledPlugins: readonly string[]
+  changedFiles: readonly string[]
+  npmDependenciesChanged: boolean
+}
+
+/** Result of committing one project edit session. */
+export interface ProjectCommitResult<TProject> {
+  project: TProject
+  changes: ChangeSet
+}