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/system.ts

@@ -0,0 +1,129 @@
+import { existsSync, readFileSync } from "node:fs"
+
+import { MIN_OPENCODE_VERSION, CHECK_IDS, CHECK_NAMES } from "../constants"
+import type { CheckResult, DoctorIssue, SystemInfo } from "../types"
+import { findOpenCodeBinary, getOpenCodeVersion, compareVersions } from "./system-binary"
+import { getPluginInfo } from "./system-plugin"
+import { getLatestPluginVersion, getLoadedPluginVersion } from "./system-loaded-version"
+import { parseJsonc } from "../../../shared"
+
+function isConfigValid(configPath: string | null): boolean {
+  if (!configPath) return true
+  if (!existsSync(configPath)) return false
+
+  try {
+    parseJsonc<Record<string, unknown>>(readFileSync(configPath, "utf-8"))
+    return true
+  } catch {
+    return false
+  }
+}
+
+function getResultStatus(issues: DoctorIssue[]): CheckResult["status"] {
+  if (issues.some((issue) => issue.severity === "error")) return "fail"
+  if (issues.some((issue) => issue.severity === "warning")) return "warn"
+  return "pass"
+}
+
+function buildMessage(status: CheckResult["status"], issues: DoctorIssue[]): string {
+  if (status === "pass") return "System checks passed"
+  if (status === "fail") return `${issues.length} system issue(s) detected`
+  return `${issues.length} system warning(s) detected`
+}
+
+export async function gatherSystemInfo(): Promise<SystemInfo> {
+  const [binaryInfo, pluginInfo] = await Promise.all([findOpenCodeBinary(), Promise.resolve(getPluginInfo())])
+  const loadedInfo = getLoadedPluginVersion()
+
+  const opencodeVersion = binaryInfo ? await getOpenCodeVersion(binaryInfo.path) : null
+  const pluginVersion = pluginInfo.pinnedVersion ?? loadedInfo.expectedVersion
+
+  return {
+    opencodeVersion,
+    opencodePath: binaryInfo?.path ?? null,
+    pluginVersion,
+    loadedVersion: loadedInfo.loadedVersion,
+    bunVersion: Bun.version,
+    configPath: pluginInfo.configPath,
+    configValid: isConfigValid(pluginInfo.configPath),
+    isLocalDev: pluginInfo.isLocalDev,
+  }
+}
+
+export async function checkSystem(): Promise<CheckResult> {
+  const [systemInfo, pluginInfo] = await Promise.all([gatherSystemInfo(), Promise.resolve(getPluginInfo())])
+  const loadedInfo = getLoadedPluginVersion()
+  const latestVersion = await getLatestPluginVersion(systemInfo.loadedVersion)
+  const issues: DoctorIssue[] = []
+
+  if (!systemInfo.opencodePath) {
+    issues.push({
+      title: "OpenCode binary not found",
+      description: "Install OpenCode CLI or desktop and ensure the binary is available.",
+      fix: "Install from https://opencode.ai/docs",
+      severity: "error",
+      affects: ["doctor", "run"],
+    })
+  }
+
+  if (
+    systemInfo.opencodeVersion &&
+    !compareVersions(systemInfo.opencodeVersion, MIN_OPENCODE_VERSION)
+  ) {
+    issues.push({
+      title: "OpenCode version below minimum",
+      description: `Detected ${systemInfo.opencodeVersion}; required >= ${MIN_OPENCODE_VERSION}.`,
+      fix: "Update OpenCode to the latest stable release",
+      severity: "warning",
+      affects: ["tooling", "doctor"],
+    })
+  }
+
+  if (!pluginInfo.registered) {
+    issues.push({
+      title: "oh-my-opencode is not registered",
+      description: "Plugin entry is missing from OpenCode configuration.",
+      fix: "Run: bunx oh-my-opencode install",
+      severity: "error",
+      affects: ["all agents"],
+    })
+  }
+
+  if (loadedInfo.expectedVersion && loadedInfo.loadedVersion && loadedInfo.expectedVersion !== loadedInfo.loadedVersion) {
+    issues.push({
+      title: "Loaded plugin version mismatch",
+      description: `Cache expects ${loadedInfo.expectedVersion} but loaded ${loadedInfo.loadedVersion}.`,
+      fix: "Reinstall plugin dependencies in OpenCode cache",
+      severity: "warning",
+      affects: ["plugin loading"],
+    })
+  }
+
+  if (
+    systemInfo.loadedVersion &&
+    latestVersion &&
+    !compareVersions(systemInfo.loadedVersion, latestVersion)
+  ) {
+    issues.push({
+      title: "Loaded plugin is outdated",
+      description: `Loaded ${systemInfo.loadedVersion}, latest ${latestVersion}.`,
+      fix: "Update: cd ~/.config/opencode && bun update oh-my-opencode",
+      severity: "warning",
+      affects: ["plugin features"],
+    })
+  }
+
+  const status = getResultStatus(issues)
+  return {
+    name: CHECK_NAMES[CHECK_IDS.SYSTEM],
+    status,
+    message: buildMessage(status, issues),
+    details: [
+      systemInfo.opencodeVersion ? `OpenCode: ${systemInfo.opencodeVersion}` : "OpenCode: not detected",
+      `Plugin expected: ${systemInfo.pluginVersion ?? "unknown"}`,
+      `Plugin loaded: ${systemInfo.loadedVersion ?? "unknown"}`,
+      `Bun: ${systemInfo.bunVersion ?? "unknown"}`,
+    ],
+    issues,
+  }
+}