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).

internal/mcp/server_test.go

@@ -1,11 +1,79 @@
 package mcp
 
 import (
+	"encoding/json"
+	"strings"
 	"testing"
 
 	"github.com/google/uuid"
+	"github.com/modelcontextprotocol/go-sdk/mcp"
 )
 
+func TestAnnotateJSONResult(t *testing.T) {
+	// valid JSON array → wrapped with __renderer + data
+	result := textResult(`[{"slug": "host:hubris", "type": "host"}]`)
+	annotated := annotateJSONResult(result, "entity_card")
+
+	if len(annotated.Content) != 1 {
+		t.Fatalf("expected 1 content item, got %d", len(annotated.Content))
+	}
+	tc, ok := annotated.Content[0].(*mcp.TextContent)
+	if !ok {
+		t.Fatal("content is not TextContent")
+	}
+
+	var wrapper map[string]interface{}
+	if err := json.Unmarshal([]byte(tc.Text), &wrapper); err != nil {
+		t.Fatalf("result is not valid JSON: %v", err)
+	}
+	if wrapper["__renderer"] != "entity_card" {
+		t.Errorf("__renderer = %q, want entity_card", wrapper["__renderer"])
+	}
+	data, ok := wrapper["data"].([]interface{})
+	if !ok || len(data) != 1 {
+		t.Fatal("data is not the original array")
+	}
+}
+
+func TestAnnotateJSONResultNoop(t *testing.T) {
+	// empty content → no-op
+	result := &mcp.CallToolResult{Content: []mcp.Content{}}
+	annotated := annotateJSONResult(result, "entity_card")
+	if len(annotated.Content) != 0 {
+		t.Fatal("empty content should be unchanged")
+	}
+
+	// non-JSON text → no-op (not wrapped)
+	result = textResult("just plain text")
+	annotated = annotateJSONResult(result, "entity_card")
+	tc, _ := annotated.Content[0].(*mcp.TextContent)
+	if strings.Contains(tc.Text, "__renderer") {
+		t.Fatal("non-JSON content should not be annotated")
+	}
+
+	// textResult with empty string → no-op
+	result = textResult("")
+	annotated = annotateJSONResult(result, "entity_card")
+	tc, _ = annotated.Content[0].(*mcp.TextContent)
+	if tc.Text != "" {
+		t.Fatal("empty text content should be unchanged")
+	}
+}
+
+func TestAnnotateJSONResultPreservesMultipleRows(t *testing.T) {
+	result := textResult(`[{"slug": "a"}, {"slug": "b"}, {"slug": "c"}]`)
+	annotated := annotateJSONResult(result, "lxc_list")
+
+	tc, _ := annotated.Content[0].(*mcp.TextContent)
+	var wrapper map[string]interface{}
+	json.Unmarshal([]byte(tc.Text), &wrapper)
+
+	data := wrapper["data"].([]interface{})
+	if len(data) != 3 {
+		t.Fatalf("expected 3 rows in data, got %d", len(data))
+	}
+}
+
 // TestNewServerRegistersTools verifies every tool registers with a valid
 // input schema. The MCP SDK panics at AddTool if a tool omits its object
 // input schema, so merely constructing the server exercises that contract —