feat(chat): MCP tool apps — custom inline renderers for 12 tools

12 of 33 MCP tools now render as rich inline cards instead of raw JSON:
EntityCard, HealthSummary, LXCList, EntityTable, KnowledgeResults,
BlastRadius, ChangeLog, FleetSnapshot, MetricChart.

Architecture:
- Server: annotateJSONResult() wraps queryRows with __renderer hints
- Registry: match/dispatch system maps tool names to Svelte components
- Chat: inline dispatch with 5-card limit, overflow to collapsed group
- ToolCallGroup: unmatched prop, hides when all matched, ARIA labels

Tests: 3 new Go tests for annotateJSONResult (wrap, no-op, multi-row).

web/src/lib/renderers/BlastRadius.svelte

@@ -0,0 +1,70 @@
+<script lang="ts">
+  import type { ToolCallResult } from '$lib/stores/chat'
+  import LoaderCircleIcon from '@lucide/svelte/icons/loader-circle'
+  import CheckIcon from '@lucide/svelte/icons/check'
+  import XIcon from '@lucide/svelte/icons/x'
+
+  let { tool }: { tool: ToolCallResult } = $props()
+
+  const rows = $derived.by(() => {
+    if (tool.type !== 'tool_result' || !tool.result) return null
+    const data = (tool.result as any).data ?? tool.result
+    return Array.isArray(data) ? data as any[] : null
+  })
+
+  const grouped = $derived.by(() => {
+    if (!rows) return null
+    const g: Record<number, string[]> = {}
+    for (const r of rows) {
+      const d = Number(r.depth) || 0
+      if (!g[d]) g[d] = []
+      g[d].push(r.slug)
+    }
+    return g
+  })
+
+  const loading = $derived(tool.type === 'tool_use')
+  const error = $derived(tool.type === 'tool_result' ? tool.error : undefined)
+  const total = $derived(rows?.length ?? 0)
+</script>
+
+{#if loading}
+  <div class="flex items-center gap-2 rounded-lg border bg-card px-3 py-2 text-xs" role="status" aria-label="Calculating blast radius">
+    <LoaderCircleIcon class="size-3 shrink-0 animate-spin text-primary" aria-hidden="true" />
+    <span class="font-medium">Blast radius</span>
+    <span class="animate-pulse text-muted-foreground">calculating…</span>
+  </div>
+{:else if error}
+  <div class="flex items-center gap-2 rounded-lg border border-destructive/30 bg-destructive/5 px-3 py-2 text-xs" role="alert" aria-label="Blast radius error">
+    <XIcon class="size-3 shrink-0 text-destructive" aria-hidden="true" />
+    <span class="font-medium">Blast radius</span>
+    <span class="text-destructive">{error}</span>
+  </div>
+{:else if grouped && total > 0}
+  <div class="rounded-lg border bg-card text-xs" aria-label="Blast radius: {total} affected entities">
+    <div class="flex items-center gap-2 px-3 py-1.5 border-b">
+      <CheckIcon class="size-3 shrink-0 text-success" aria-hidden="true" />
+      <span class="font-medium">{total} affected entit{total === 1 ? 'y' : 'ies'}</span>
+    </div>
+    <div class="max-h-56 overflow-y-auto divide-y">
+      {#each Object.entries(grouped).sort(([a], [b]) => Number(a) - Number(b)) as [depth, slugs]}
+        <div class="px-3 py-2">
+          <div class="mb-1 font-medium text-muted-foreground">
+            {Number(depth) === 1 ? 'Directly affected' : `${depth} hops`} ({slugs.length})
+          </div>
+          <div class="flex flex-wrap gap-1">
+            {#each slugs as slug}
+              <span class="rounded bg-muted px-1.5 py-0.5 font-mono text-[10px]">{slug}</span>
+            {/each}
+          </div>
+        </div>
+      {/each}
+    </div>
+  </div>
+{:else}
+  <div class="flex items-center gap-2 rounded-lg border bg-card px-3 py-2 text-xs" role="status" aria-label="Blast radius: no affected entities">
+    <CheckIcon class="size-3 shrink-0 text-success" aria-hidden="true" />
+    <span class="font-medium">Blast radius</span>
+    <span class="text-muted-foreground">no affected entities found</span>
+  </div>
+{/if}