fix: allow agent workspace directories in media local roots

Modifies getDefaultLocalRoots() to dynamically scan STATE_DIR for
workspace-* directories (e.g., workspace-<agentId>) and include them
in the allowed local roots for media file access.

This fixes the issue where the message tool rejects file attachments
from agent-specific workspace directories like ~/.openclaw/workspace-clawdy/.

Fixes openclaw/openclaw#17133

src/web/media.ts

@@ -1,3 +1,4 @@
+import fsSync from "node:fs";
 import fs from "node:fs/promises";
 import os from "node:os";
 import path from "node:path";
@@ -34,14 +35,44 @@ type WebMediaOptions = {
   readFile?: (filePath: string) => Promise<Buffer>;
 };
 
+/**
+ * Scans STATE_DIR for agent workspace directories matching the pattern "workspace-*"
+ * and returns them as additional allowed local roots.
+ */
+function getAgentWorkspaceDirsSync(): string[] {
+  try {
+    // Note: Synchronous scan on each call - acceptable for now since this is only
+    // used when validating local media paths, which is not a hot path.
+    // For better performance, could add caching with invalidation.
+    const entries = fsSync.readdirSync(STATE_DIR, { withFileTypes: true });
+    return entries
+      .filter(
+        (entry) =>
+          entry.isDirectory() &&
+          entry.name.startsWith("workspace-") &&
+          // Exclude the default "workspace" directory (handled separately)
+          entry.name !== "workspace",
+      )
+      .map((entry) => path.join(STATE_DIR, entry.name));
+  } catch {
+    // If STATE_DIR doesn't exist or isn't readable, return empty array
+    return [];
+  }
+}
+
 export function getDefaultLocalRoots(): readonly string[] {
-  return [
+  const staticRoots = [
     os.tmpdir(),
     path.join(STATE_DIR, "media"),
     path.join(STATE_DIR, "agents"),
     path.join(STATE_DIR, "workspace"),
     path.join(STATE_DIR, "sandboxes"),
   ];
+
+  // Dynamically discover agent workspace directories (e.g., workspace-<agentId>)
+  const workspaceDirs = getAgentWorkspaceDirsSync();
+
+  return [...staticRoots, ...workspaceDirs];
 }
 
 async function assertLocalMediaAllowed(