feat(case-files): פאנל "קבצי-התיק" בטאב טיוטות — גישה מה-UI לכל תתי-התיקיות

היו"ר לא יכל לגשת לטיוטה שהסוכן שמר בדיסק (interim-decision-draft.md) אלא ב-SSH.
מימוש מוקאפ X17 מאושר (18m): פאנל דפדפן-קבצים בטאב "טיוטות והערות".

Backend (web/app.py) — הכללה של ה-endpoints הקיימים ל**כל** תת-תיקייה:
- `_case_file_folders` — מונה כל תת-תיקיית-תוכן תחת התיק (מקור/מחולץ/מחקר/הגהה/
  טיוטות/גיבויים), רקורסיה שכבה אחת לתוך documents/, מדלג על מוסתרות (.git/.claude)
  ו-thumbnails. `_resolve_case_file` מאמת folder-key מול הרשימה + חוסם path-traversal.
- `/local-files` מחזיר את כל התיקיות (כולל ריקות, עם files=[]); `/local-files/{folder}/{filename}`
  מגיש מכל תיקייה עם media-type לפי סיומת.

Frontend:
- `lib/api/case-files.ts` — useCaseFiles / useCaseFileText / caseFileUrl.
- `CaseFilesBrowser` — עץ-תיקיות (אקורדיון, ריקות מסומנות "ריק") + viewer מובנה
  ל-md/txt (Markdown הקיים) + הורדה לכל קובץ. נטען בטאב "טיוטות והערות".

אין response_model → אין תלות ב-api:types (מודול טיפוסים בכתב-יד).
Invariants: G1, G2 (אין מסלול-קבצים מקביל — מכליל את הקיים), אבטחת-נתיב.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

web/app.py

@@ -3069,42 +3069,82 @@ async def api_learn(case_number: str):
 # ── Local files API — research, drafts, proofread ──
 
 
+# Directories under a case that are infrastructure/cache, not chair-facing
+# content. Hidden dirs (``.git``, ``.claude`` …) are skipped separately.
+_CASE_FILE_EXCLUDE_DIRS = {"thumbnails"}
+
+
+def _is_content_dir(p: Path) -> bool:
+    return p.is_dir() and not p.name.startswith(".") and p.name not in _CASE_FILE_EXCLUDE_DIRS
+
+
+def _case_file_folders(case_dir: Path) -> list[tuple[str, Path]]:
+    """Enumerate every content subdirectory under a case dir as (key, path).
+
+    Covers *all* subfolders (not just research) — recursing one level into
+    ``documents/`` — while skipping hidden (``.git``/``.claude``…) and cache
+    dirs. The ``key`` is the case-relative path with ``/`` encoded as ``__`` so
+    it survives a single URL path segment; ``_resolve_case_file`` re-validates it
+    against this same enumeration, so the key set is the serve allowlist (no path
+    traversal).
+    """
+    folders: list[tuple[str, Path]] = []
+    if not case_dir.exists():
+        return folders
+    for child in sorted(case_dir.iterdir()):
+        if not _is_content_dir(child):
+            continue
+        if child.name == "documents":
+            folders.extend(
+                (f"documents__{sub.name}", sub)
+                for sub in sorted(child.iterdir())
+                if _is_content_dir(sub)
+            )
+        else:
+            folders.append((child.name, child))
+    return folders
+
+
+def _resolve_case_file(case_dir: Path, folder_key: str, filename: str) -> Path | None:
+    """Safely resolve (folder_key, filename) to a file inside the case dir.
+
+    Returns None unless ``folder_key`` is one of the enumerated content folders
+    AND ``filename`` resolves to a regular file directly inside it (no traversal).
+    """
+    base = dict(_case_file_folders(case_dir)).get(folder_key)
+    if base is None:
+        return None
+    target = (base / filename).resolve()
+    if target.parent != base.resolve() or not target.is_file():
+        return None
+    return target
+
+
 @app.get("/api/cases/{case_number}/local-files")
 async def api_local_files(case_number: str):
-    """List local files from case subdirectories (research, drafts, proofread)."""
+    """List local files across ALL content subfolders under a case (not just
+    research) — so the chair can reach any agent-produced file (drafts, OCR text,
+    originals…) from the UI instead of only over SSH. Empty folders are returned
+    too (with an empty ``files`` list) so the UI can show them as such."""
     case_dir = config.find_case_dir(case_number)
-    result = {}
-    for folder in ("research", "proofread"):
-        folder_path = case_dir / "documents" / folder
-        if folder_path.exists():
-            files = []
-            for f in sorted(folder_path.iterdir()):
-                if f.is_file() and not f.name.startswith("."):
-                    stat = f.stat()
-                    files.append({
-                        "filename": f.name,
-                        "size": stat.st_size,
-                        "modified_at": stat.st_mtime,
-                        "folder": folder,
-                    })
-            if files:
-                result[folder] = files
-    # Drafts are at case level, not under documents
-    drafts_path = case_dir / "drafts"
-    if drafts_path.exists():
+    folders = []
+    for key, path in _case_file_folders(case_dir):
         files = []
-        for f in sorted(drafts_path.iterdir()):
+        for f in sorted(path.iterdir()):
             if f.is_file() and not f.name.startswith("."):
                 stat = f.stat()
                 files.append({
                     "filename": f.name,
                     "size": stat.st_size,
                     "modified_at": stat.st_mtime,
-                    "folder": "drafts",
                 })
-        if files:
-            result["drafts"] = files
-    return result
+        folders.append({
+            "key": key,
+            "name": path.name,
+            "path": str(path.relative_to(case_dir)),
+            "files": files,
+        })
+    return {"folders": folders}
 
 
 async def serve_blob(
@@ -3174,17 +3214,32 @@ async def _seal_blob_file(dest: Path, *, bucket=storage.Bucket.DOCUMENTS) -> Non
 
 @app.get("/api/cases/{case_number}/local-files/{folder}/{filename}")
 async def api_read_local_file(case_number: str, folder: str, filename: str):
-    """Read contents of a local case file."""
-    if folder not in ("research", "proofread", "drafts"):
-        raise HTTPException(400, "Invalid folder")
+    """Serve a single local case file from any content subfolder.
+
+    ``folder`` is a key from ``/local-files`` (``documents__research``, ``drafts``…);
+    ``_resolve_case_file`` validates it against the folder allowlist and blocks
+    path traversal before the bytes are served.
+    """
     case_dir = config.find_case_dir(case_number)
-    if folder == "drafts":
-        path = case_dir / "drafts" / filename
-    else:
-        path = case_dir / "documents" / folder / filename
-    if not path.exists() or not path.is_file():
+    path = _resolve_case_file(case_dir, folder, filename)
+    if path is None:
         raise HTTPException(404, "קובץ לא נמצא")
-    return await serve_blob(path, media_type="text/plain; charset=utf-8", filename=filename)
+    media_type = _local_file_media_type(filename)
+    return await serve_blob(path, media_type=media_type, filename=filename)
+
+
+def _local_file_media_type(filename: str) -> str:
+    """Best-effort content type for a served case file (text renders inline,
+    binaries download)."""
+    ext = filename.rsplit(".", 1)[-1].lower() if "." in filename else ""
+    return {
+        "md": "text/markdown; charset=utf-8",
+        "txt": "text/plain; charset=utf-8",
+        "json": "application/json; charset=utf-8",
+        "pdf": "application/pdf",
+        "docx": "application/vnd.openxmlformats-officedocument.wordprocessingml.document",
+        "doc": "application/msword",
+    }.get(ext, "application/octet-stream")
 
 
 # ── Research analysis (analysis-and-research.md) — parse + edit ────