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/scripts/src/command.ts

@@ -0,0 +1,76 @@
+/**
+ * Internal dsh-sdk command composition used by the package bin.
+ *
+ * @module @deepseek-ai/dsh-scripts/command
+ */
+
+import { parseDshSdkArgs } from './args.ts'
+import { runProjectBuild } from './build.ts'
+import { runConfigCommand, type ConfigCommandContext } from './config.ts'
+import { runCreatePluginCommand } from './create-plugin.ts'
+import { runSDK } from './runtime.ts'
+import { reportCommandTelemetry, type CommandTelemetryEvent } from './telemetry.ts'
+import { DSH_SDK_TEMPLATES } from './templates/dsh-sdk-templates.ts'
+
+/** Injectable process and command boundaries used by the dsh-sdk bin. */
+export interface DshSdkCommandContext extends ConfigCommandContext {
+  cwd: string
+  stdin: NodeJS.ReadStream
+  stdout: NodeJS.WriteStream
+  stderr: NodeJS.WriteStream
+  run?: typeof runSDK
+  build?: typeof runProjectBuild
+  config?: typeof runConfigCommand
+  createPlugin?: typeof runCreatePluginCommand
+  telemetry?: (event: CommandTelemetryEvent) => Promise<void>
+}
+
+/** Run one parsed dsh-sdk command and return its process exit code. */
+export async function runDshSdkCommand(
+  argv: readonly string[] = process.argv.slice(2),
+  context: DshSdkCommandContext = {
+    cwd: process.cwd(),
+    stdin: process.stdin,
+    stdout: process.stdout,
+    stderr: process.stderr,
+  },
+): Promise<number> {
+  const startedAt = Date.now()
+  let command: string | undefined
+  let success = true
+  try {
+    const args = parseDshSdkArgs(argv)
+    if (args.help || !args.command) {
+      context.stdout.write(DSH_SDK_TEMPLATES.usage.render({}))
+      return 0
+    }
+    command = args.command
+    const run = context.run ?? runSDK
+    const build = context.build ?? runProjectBuild
+    const config = context.config ?? runConfigCommand
+    const createPlugin = context.createPlugin ?? runCreatePluginCommand
+    switch (args.command) {
+      case 'start': await run(args.target, { cwd: context.cwd, argv: args.forwarded }); break
+      case 'dev': await run(args.target, { cwd: context.cwd, dev: true, argv: args.forwarded }); break
+      case 'build': await build(args.forwarded, context.cwd); break
+      case 'config': {
+        const result = await config(context)
+        if (result.installError) { success = false; return 1 }
+        break
+      }
+      /* v8 ignore next -- Commander requires <source>, so create never dispatches without it */
+      case 'create': await createPlugin(args.source ?? '', context); break
+    }
+    return 0
+  } catch (error) {
+    success = false
+    context.stderr.write(`dsh-sdk: ${error instanceof Error ? error.message : String(error)}\n`)
+    return 1
+  } finally {
+    if (command !== undefined) {
+      /* v8 ignore next -- production telemetry wiring is exercised by the built-bin smoke */
+      const telemetry = context.telemetry ?? reportCommandTelemetry
+      await telemetry({ command, cwd: context.cwd, durationMs: Date.now() - startedAt, success })
+    }
+  }
+}