refactor(doctor): redesign with 3-tier output and consolidated checks

Consolidate 16 separate checks into 5 (system, config, providers, tools, models).
Add 3-tier formatting: default (problems-only), --status (dashboard), --verbose (deep diagnostics).
Read actual loaded plugin version from opencode cache directory.
Check environment variables for provider authentication.

src/cli/doctor/checks/tools-mcp.ts

@@ -0,0 +1,62 @@
+import { existsSync, readFileSync } from "node:fs"
+import { homedir } from "node:os"
+import { join } from "node:path"
+
+import type { McpServerInfo } from "../types"
+import { parseJsonc } from "../../../shared"
+
+const BUILTIN_MCP_SERVERS = ["context7", "grep_app"]
+
+interface McpConfigShape {
+  mcpServers?: Record<string, unknown>
+}
+
+function getMcpConfigPaths(): string[] {
+  return [
+    join(homedir(), ".claude", ".mcp.json"),
+    join(process.cwd(), ".mcp.json"),
+    join(process.cwd(), ".claude", ".mcp.json"),
+  ]
+}
+
+function loadUserMcpConfig(): Record<string, unknown> {
+  const servers: Record<string, unknown> = {}
+
+  for (const configPath of getMcpConfigPaths()) {
+    if (!existsSync(configPath)) continue
+
+    try {
+      const content = readFileSync(configPath, "utf-8")
+      const config = parseJsonc<McpConfigShape>(content)
+      if (config.mcpServers) {
+        Object.assign(servers, config.mcpServers)
+      }
+    } catch {
+      continue
+    }
+  }
+
+  return servers
+}
+
+export function getBuiltinMcpInfo(): McpServerInfo[] {
+  return BUILTIN_MCP_SERVERS.map((serverId) => ({
+    id: serverId,
+    type: "builtin",
+    enabled: true,
+    valid: true,
+  }))
+}
+
+export function getUserMcpInfo(): McpServerInfo[] {
+  return Object.entries(loadUserMcpConfig()).map(([serverId, value]) => {
+    const valid = typeof value === "object" && value !== null
+    return {
+      id: serverId,
+      type: "user",
+      enabled: true,
+      valid,
+      error: valid ? undefined : "Invalid configuration format",
+    }
+  })
+}