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).

docs/core-data-structures/commands.md

@@ -2,9 +2,9 @@
 
 English | [中文](commands.zh.md)
 
-The human-command seam of [`dsh-commands`](../../packages/ui/commands). Interactive adapters use it to discover and directly execute plugin-owned commands for an exact agent without creating a model message. The [command Agent Note](../../.agents/notes/implemented/feature/2026-07-19-plugin-command-registration.md) owns dispatch and lifecycle rationale; the [package README](../../packages/ui/commands/README.md) owns composition and limitations.
+The human-command seam of [`dsh-commands`](../../packages/interaction/commands). Interactive adapters use it to discover and directly execute plugin-owned commands for an exact agent without creating a model message. The [command Agent Note](../../.agents/notes/implemented/feature/2026-07-19-plugin-command-registration.md) owns dispatch and lifecycle rationale; the [package README](../../packages/interaction/commands/README.md) owns composition and limitations.
 
-Source: [`packages/ui/commands/src/index.ts`](../../packages/ui/commands/src/index.ts)
+Source: [`packages/interaction/commands/src/index.ts`](../../packages/interaction/commands/src/index.ts)
 
 ## Input metadata