chore(baseline): target DSH 0.1.6-alpha.2 and drop 0.1.5-rc support

The peer floor had to move: semver's prerelease rule needs a comparator on the
same [major,minor,patch] tuple, so `^0.1.5-rc.1` can never match any 0.1.6
prerelease. The floor becomes `^0.1.6-alpha.2` (which does admit 0.1.6 alpha/rc
prereleases and excludes 0.1.5), and `engines.dsh` follows. This is a deliberate
support-line break, matching how v0.19.0 dropped 0.1.2: 0.1.5-rc hosts stay on
0.19.1.

Three upstream changes actually reach this plugin and are adapted here:

- `IconSendOutline16` no longer exists in ui-primitives (only
  `IconSendOutline14`).
- `TerminalBlockLabels` gained a required `noExitCode` pill text.
- `ConnectionIndicator` dropped `reconnectLabel`: the outage label is now the
  one static label that already names the retry action, so the label copy moves
  there, matching the host's own '连接异常，点击立即重连'.

ui-primitives still declares no `dependencies` while its bundle bare-imports
more than it used to: `diff` and `simple-icons` were previously satisfied only
transitively and had to be hoisted into devDependencies, exactly like the
anser/shiki/katex group before them. `@deepseek-ai/dsh-code-runtime` is gone
upstream (the package no longer exists) and leaves the dev tree.

The e2e fallback npx spec is pinned rather than version-less: an unpinned
`npx @deepseek-ai/dsh` resolves npm's `latest`, which is still the 0.1.5 line
this plugin no longer supports.

.github/workflows/ci.yml

@@ -151,15 +151,15 @@ jobs:
       # Pin the DSH CLI the lane mounts into; the profile's bundle stack
       # (dsh-base / dsh-web-app) resolves from this installation. Keep in
       # step with the plugin's @deepseek-ai/* peer range when bumping.
-      # DSH 0.1.5-rc.2 is the `next` dist-tag on npm (`latest` still points
-      # at rc.1); the lanes speak the slash-only RPC dialect
+      # DSH 0.1.6-alpha.2 is the `alpha` dist-tag on npm (`latest` is still
+      # the 0.1.5 line); the lanes speak the slash-only RPC dialect
       # (tests/e2e/host-protocol.ts).
       #
       # The larger heap is the fix for one of the two ways this step used to
       # die (runs 34490912649 and 34363627184 on the alpha line): the pinned
       # version's TRANSITIVES are declared as floating `^` ranges, so while
       # upstream publishes a prerelease in stages (0.1.5-rc.2 went out
-      # 14:43-14:57 on 2026-09-10) npm resolved a mixed rc.1/rc.2 peer graph —
+      # 14:43-14:57 on 2026-09-10) npm resolved a mixed peer graph —
       # 3062 ERESOLVE lines, then "Ineffective mark-compacts near heap limit"
       # (exit 134). The other failure mode was a hard ETARGET on a sibling
       # package that appeared minutes later; pinning a version that is fully
@@ -175,7 +175,7 @@ jobs:
       - name: Install dsh CLI (pinned)
         env:
           NODE_OPTIONS: --max-old-space-size=4096
-        run: npm install -g @deepseek-ai/dsh@0.1.5-rc.2
+        run: npm install -g @deepseek-ai/dsh@0.1.6-alpha.2
 
       # lib/ is gitignored; the tarball is produced from this build.
       - name: Build and pack the npm tarball