feat: adapt to DSH 0.1.7-rc.1

Move the support line from 0.1.7-alpha.1 to 0.1.7-rc.1 (peer floor
`^0.1.7-rc.1`). 0.21.0-alpha.1 never reached npm, and once the code-card
labels below are fixed the same build crashes on alpha.1 (its DiffBlock
still reads the `labels.files` upstream deleted), so declaring only the
host we verify against is the honest floor — and from rc.1 on the host
enforces peers at boot anyway: a row whose `@deepseek-ai/dsh-*` peers do
not satisfy the runtime is silently disabled.

Dependencies: 28 devDependency pins and 14 peers move to 0.1.7-rc.1.
rc.1 also raised the vendored runtime (cordis 4.0.4, schemastery 3.18.4,
cordis-plugin-group 1.0.4, cordis-plugin-include 1.0.9) and publishes DSH
cross-references as exact versions, so bumping schemastery/cordis alone
left four unmet transitive peers — the three vendor packages are hoisted
into devDependencies, which is what makes `pnpm peers check` clean again.

One compile break: rc.1 added `CodeToolbarLabels` (codeLabel / wrapLabel /
unwrapLabel, all required), made DiffBlockLabels / ReadBlockLabels extend
it and deleted `DiffBlockLabels.files`. Fixing SideChatView then leaving
markdown on the legacy banner would render two different code-card styles
inside one side-chat view, so the plugin adopts the card everywhere:
`markdownTextProps()` now passes `labels.code.toolbarLabels` with the
host's own wording (codeBlock.title|wrap|unwrap, added to all 20
dictionaries; `sideChatBlockFiles` retires with the deleted footer).

Adopting the card surfaced a silent regression the suite caught: the new
toolbar shows `codeLabel` for languages the highlighter does not know, and
mermaid has no shiki grammar, so the info string no longer reaches the DOM
and the banner-text probe in mermaid.tsx matched nothing — mermaid fences
stopped being swapped for diagrams. Detection now matches the FENCE BODY
from the source that produced the render.

`tests/market-manifest.spec.ts` pins every DSH peer as a floating caret
range: an exact pin (the devDependency style) or a comparator without a
prerelease would fail rc.1's preflight and silently stop the plugin from
loading, and `pnpm peers check` cannot see that — it validates the
resolved dev tree, not the range shape the host reads.

src/client/changes/DiffPane.tsx

@@ -108,7 +108,13 @@ function PaneToggle(props: { on: boolean; label: string; title?: string; onClick
  *  lifted out); the plain path stays byte-for-byte for documents without
  *  any. */
 function MdReadingView(props: { text: string }) {
-  const codeLabels = { copyLabel: t('copy'), copiedLabel: t('copied') }
+  const codeLabels = {
+    copyLabel: t('copy'),
+    copiedLabel: t('copied'),
+    codeLabel: t('codeBlockTitle'),
+    wrapLabel: t('codeBlockWrap'),
+    unwrapLabel: t('codeBlockUnwrap'),
+  }
   const hasMermaid = splitMermaidBlocks(props.text).some((block) => block.kind === 'mermaid')
   return (
     <div className={css.paneBody}>