feat: replace SFTP drop with Syncthing share path

Remove SFTPGo; mount event data from the Syncthing folder, watch
incoming/, and name variants after the source stem.

Co-authored-by: Cursor <cursoragent@cursor.com>

app/worker.py

@@ -1,8 +1,8 @@
-"""Inbox watcher + sequential job runner.
+"""Incoming watcher + sequential job runner.
 
-Polls `DATA_DIR/inbox` for new, size-stable image files, copies each one
+Polls `DATA_DIR/incoming` for new, size-stable image files, copies each one
 into its own `jobs/<job_id>/original.*` and runs the compose pipeline on
-it. Files are NEVER deleted or moved from the inbox — `processed.json`
+it. Files are NEVER deleted or moved from incoming — `processed.json`
 tracks what has already been handled (by path + size + mtime) so restarts
 don't reprocess everything.
 
@@ -61,9 +61,18 @@ def _is_already_processed(processed: dict[str, Any], path: Path, stat: Any) -> b
     return entry.get("size") == stat.st_size and entry.get("mtime") == stat.st_mtime
 
 
+def _is_ignored_name(name: str) -> bool:
+    """Skip Syncthing metadata/temp files and other dotfiles."""
+    if name.startswith("."):
+        return True
+    if name.startswith(".syncthing.") or ".syncthing." in name:
+        return True
+    return False
+
+
 def _is_stable(path: Path) -> bool:
     """A file is "stable" if its size doesn't change across a short wait —
-    cheap way to avoid picking up a half-uploaded SFTP transfer."""
+    cheap way to avoid picking up a half-written Syncthing transfer."""
     try:
         size_before = path.stat().st_size
     except OSError:
@@ -77,12 +86,15 @@ def _is_stable(path: Path) -> bool:
 
 
 def find_new_files(processed: dict[str, Any]) -> list[Path]:
+    """Top-level images under incoming/ only — never recurse into jobs/."""
     if not config.INBOX_DIR.exists():
         return []
     candidates: list[Path] = []
-    for path in sorted(config.INBOX_DIR.rglob("*")):
+    for path in sorted(config.INBOX_DIR.iterdir()):
         if not path.is_file():
             continue
+        if _is_ignored_name(path.name):
+            continue
         if path.suffix.lower() not in config.SUPPORTED_EXTENSIONS:
             continue
         try:
@@ -105,13 +117,14 @@ def handle_file(path: Path, processed: dict[str, Any]) -> None:
     suffix = path.suffix.lower()
     paths = pipeline.job_paths(job_id, suffix)
     paths.root.mkdir(parents=True, exist_ok=True)
+    source_stem = pipeline.sanitize_stem(path.stem)
 
-    logger.info("new inbox file %s -> job %s", path.name, job_id)
-    # Copy (never move) so the inbox stays untouched.
+    logger.info("new incoming file %s -> job %s (stem=%s)", path.name, job_id, source_stem)
+    # Copy (never move) so incoming stays untouched.
     shutil.copy2(path, paths.original)
 
     try:
-        pipeline.process_job(job_id, paths.original, suffix)
+        pipeline.process_job(job_id, paths.original, suffix, source_stem=source_stem)
     finally:
         # Mark as processed regardless of pipeline outcome so a permanently
         # broken image doesn't get retried forever; failures are visible in