feat: use storagePath config for plugin data directory

All plugin files (lock, logs) now live under the configured storage
path (default ~/.local/share/opencode-matrix-bot/plugin-data),
matching matrix-client.ts behavior. No extra directories created.

index.ts

@@ -1,25 +1,34 @@
 import fs from "fs"
 import os from "os"
+import path from "path"
 import { MatrixBotClient } from "./matrix-client.js"
 import { SessionManager } from "./session-manager.js"
 import { loadConfig } from "./config-loader.js"
 import { log } from "./logger.js"
 
-const PLUGIN_DATA_DIR = `${os.homedir()}/.opencode-matrix-plugin`
-if (!fs.existsSync(PLUGIN_DATA_DIR)) {
-  fs.mkdirSync(PLUGIN_DATA_DIR, { recursive: true })
-}
-const LOG_FILE = `${PLUGIN_DATA_DIR}/plugin.log`
-const SETUP_STARTED_LOG = `${PLUGIN_DATA_DIR}/setup-started.log`
-const SETUP_ERROR_LOG = `${PLUGIN_DATA_DIR}/setup-error.log`
-const LOCK_FILE = `${PLUGIN_DATA_DIR}/lock`
-
 log("Plugin module loaded")
 
+// =============================================================================
+// Plugin data directory — uses the same default as matrix-client
+// =============================================================================
+
+function getPluginDataDir(options: any): string {
+  const storagePath = options.storagePath || path.join(os.homedir(), ".local", "share", "opencode-matrix-bot")
+  return path.join(storagePath, "plugin-data")
+}
+
+function ensureDataDir(dir: string): void {
+  if (!fs.existsSync(dir)) {
+    fs.mkdirSync(dir, { recursive: true })
+  }
+}
+
 // =============================================================================
 // Global mutex — prevents double startup (server + client both load plugins)
 // =============================================================================
 
+let LOCK_FILE = ""
+
 function tryAcquireLock(): boolean {
   try {
     // Check if an existing lock is stale (process no longer running)
@@ -59,6 +68,12 @@ function releaseLock(): void {
 // =============================================================================
 
 async function runPlugin(ctx: any, options: any) {
+  const dataDir = getPluginDataDir(options)
+  ensureDataDir(dataDir)
+  LOCK_FILE = `${dataDir}/lock`
+  const SETUP_STARTED_LOG = `${dataDir}/setup-started.log`
+  const SETUP_ERROR_LOG = `${dataDir}/setup-error.log`
+
   // Acquire global lock — only one instance (server or client) starts the bot
   const locked = tryAcquireLock()
   if (!locked) {
@@ -289,7 +304,12 @@ async function v2Setup(ctx: any) {
     const { options } = await loadConfig(ctx.options)
     return await runPlugin(ctx, options)
   } catch (err) {
-    fs.appendFileSync(SETUP_ERROR_LOG, `[${new Date().toISOString()}] ${String(err)}\n`)
+    const rawStorage = (ctx.options as any)?.storagePath
+    const dataDir = rawStorage
+      ? path.join(rawStorage, "plugin-data")
+      : path.join(os.homedir(), ".local", "share", "opencode-matrix-bot", "plugin-data")
+    ensureDataDir(dataDir)
+    fs.appendFileSync(`${dataDir}/setup-error.log`, `[${new Date().toISOString()}] ${String(err)}\n`)
     log(`V2 setup error: ${String(err)}`)
     return () => {}
   }