fix(wiki): add fail-closed option for empty source-path allow-list

mateclaw-server/src/main/java/vip/mate/wiki/WikiProperties.java

@@ -80,6 +80,16 @@ public class WikiProperties {
      */
     private java.util.List<String> allowedSourceRoots = new java.util.ArrayList<>();
 
+    /**
+     * Fail-closed switch for source-path validation. When {@code true} and
+     * {@link #allowedSourceRoots} is empty, every source directory is rejected
+     * (no path is allowed until a root is configured) — recommended for
+     * multi-tenant servers so a missing allow-list cannot silently re-open
+     * full-filesystem reads. Default {@code false} keeps the opt-in behaviour
+     * for desktop / single-tenant where no roots are configured.
+     */
+    private boolean requireAllowedRoots = false;
+
     /**
      * When {@code true}, a scheduled job (single-owner via ShedLock) scans each
      * KB's configured source directory and auto-ingests new files. Off by

mateclaw-server/src/main/java/vip/mate/wiki/service/WikiSourcePathValidator.java

@@ -47,6 +47,11 @@ public class WikiSourcePathValidator {
         Path resolved = canonicalize(Paths.get(rawPath));
         List<String> roots = properties.getAllowedSourceRoots();
         if (roots == null || roots.isEmpty()) {
+            if (properties.isRequireAllowedRoots()) {
+                throw new IllegalArgumentException(
+                        "No allowed source roots are configured; refusing the path (fail-closed). "
+                        + "Set mate.wiki.allowed-source-roots to permit directories.");
+            }
             return resolved;
         }
         for (String root : roots) {

mateclaw-server/src/test/java/vip/mate/wiki/service/WikiSourcePathValidatorTest.java

@@ -27,6 +27,12 @@ class WikiSourcePathValidatorTest {
         return new WikiSourcePathValidator(props);
     }
 
+    private WikiSourcePathValidator failClosedValidator() {
+        WikiProperties props = new WikiProperties();
+        props.setRequireAllowedRoots(true);
+        return new WikiSourcePathValidator(props);
+    }
+
     @Test
     void blankPath_rejected() {
         assertThrows(IllegalArgumentException.class, () -> validator(List.of()).validateDirectory(" "));
@@ -38,6 +44,13 @@ class WikiSourcePathValidatorTest {
         assertEquals(tmp.toRealPath(), resolved);
     }
 
+    @Test
+    void emptyRoots_failClosed_rejectsEverything(@TempDir Path tmp) {
+        // With require-allowed-roots enabled, an empty allow-list denies all.
+        assertThrows(IllegalArgumentException.class,
+                () -> failClosedValidator().validateDirectory(tmp.toString()));
+    }
+
     @Test
     void insideAllowedRoot_isAccepted(@TempDir Path root) throws IOException {
         Path sub = Files.createDirectory(root.resolve("kb-source"));