fix(node): index, serve and write files past Windows' MAX_PATHHEADmain

With the system's default setting (LongPathsEnabled off) every call given
a plain path of 260 characters or more refuses it, so a deep library was
partly invisible: the walk could not list such a directory and its files
never reached the members.

The node now hands each call that touches a group's disk the extended
form (paths.long_path), and keeps the plain path in the index, the hash
cache and the log. A directory is listed under its long form and its
entries named from the plain one (indexer.walk_files, wire._walk_dirs).
Covered: the walk, stats and hashing, reconcile and the watcher, the
folder list members see, serving over WebRTC and QUIC, deletion, uploads
and their recovery, folder creation and removal, audio tags and the
cover beside a track, photos, and a show's episode numbering. ffmpeg
extends a long path itself and keeps the plain one.

long_path now normalises before prefixing (the extended form skips the
system's normalisation) and starts at 248 characters, where creating a
directory is already refused.

test_long_paths.py runs with the setting off: 15 of its 17 tests fail
without the change. Checked by hand in the installed app with files at
312 to 380 characters.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

1 files changed, 9 insertions, 4 deletions

diff --git a/packages/meshbay-node/src/meshbay_node/uploads.py b/packages/meshbay-node/src/meshbay_node/uploads.py
index c485e39..a0f65dc 100644
--- a/packages/meshbay-node/src/meshbay_node/uploads.py
+++ b/packages/meshbay-node/src/meshbay_node/uploads.py
@@ -24,6 +24,7 @@ build first.
 
 from __future__ import annotations
 
+import os
 import re
 import secrets
 import time
@@ -31,6 +32,10 @@ from collections.abc import Iterable
 from dataclasses import dataclass, field
 from pathlib import Path
 
+from meshbay_common.paths import long_path
+
+from meshbay_node.indexer.indexer import walk_files
+
 # What an unfinished upload is called on disk while it is being written. The
 # node has always used this; it is named here because the reaper below has to
 # recognise one, and a second spelling of it would be a bug nobody could see.
@@ -208,14 +213,14 @@ def find_parts(roots: Iterable) -> list[tuple[Path, float]]:
         if not getattr(root, "available", False):
             continue
         try:
-            candidates = root.path.rglob(f"*{PART_SUFFIX}")
+            candidates = walk_files(root.path)
         except OSError:
             continue
         for path in candidates:
+            if not path.name.endswith(PART_SUFFIX):
+                continue
             try:
-                if not path.is_file():
-                    continue
-                found.append((path, path.stat().st_mtime))
+                found.append((path, os.stat(long_path(path)).st_mtime))
             except OSError:
                 continue
     return found