fix: add configSchema to openclaw.plugin.json, add search CLI command, fix total_docs stat

- Add required configSchema to openclaw.plugin.json for OpenClaw plugin discovery
- Add search command to CLI with --limit, --dir, --from-date, --to-date, --tags filters
- Fix get_stats() to properly count unique docs (was returning 0 for non-null values)
- Remove hardcoded max_results default of 5; search now returns all results by default
- Update INSTALL.md and design docs with correct OpenClaw extension path instructions

python/obsidian_rag/vector_store.py

@@ -117,7 +117,7 @@ def delete_by_source_file(table: Any, source_file: str) -> int:
 def search_chunks(
     table: Any,
     query_vector: list[float],
-    limit: int = 5,
+    limit: int | None = None,
     directory_filter: list[str] | None = None,
     date_range: dict | None = None,
     tags: list[str] | None = None,
@@ -132,7 +132,7 @@ def search_chunks(
     conditions: list[str] = []
     if directory_filter:
         dir_list = ", ".join(f'"{d}"' for d in directory_filter)
-        conditions.append(f'source_directory IN ({dir_list})')
+        conditions.append(f"source_directory IN ({dir_list})")
     if date_range:
         if "from" in date_range:
             conditions.append(f"date >= '{date_range['from']}'")
@@ -144,11 +144,13 @@ def search_chunks(
 
     where_clause = " AND ".join(conditions) if conditions else None
 
-    results = (
-        table.search(query_vector, vector_column_name="vector")
-        .limit(limit)
-        .where(where_clause) if where_clause else table.search(query_vector, vector_column_name="vector").limit(limit)
-    ).to_list()
+    search_query = table.search(query_vector, vector_column_name="vector")
+    if limit is not None:
+        search_query = search_query.limit(limit)
+    if where_clause:
+        search_query = search_query.where(where_clause)
+
+    results = search_query.to_list()
 
     return [
         SearchResult(
@@ -156,7 +158,9 @@ def search_chunks(
             chunk_text=r["chunk_text"],
             source_file=r["source_file"],
             source_directory=r["source_directory"],
-            section=r.get("section") if r.get("section") not in (None, "None") else None,
+            section=r.get("section")
+            if r.get("section") not in (None, "None")
+            else None,
             date=r.get("date") if r.get("date") not in (None, "None") else None,
             tags=r.get("tags") or [],
             chunk_index=r.get("chunk_index") or 0,
@@ -172,10 +176,17 @@ def get_stats(table: Any) -> dict[str, Any]:
     total_chunks = 0
     try:
         total_chunks = table.count_rows()
-        # Count unique source files using pandas
+        # Count non-null, non-empty source files
         all_data = table.to_pandas()
-        total_docs = all_data["source_file"].nunique()
+        total_docs = (
+            all_data["source_file"]
+            .dropna()
+            .astype(str)
+            .str.strip()
+            .loc[lambda s: s.str.len() > 0]
+            .nunique()
+        )
     except Exception:
         pass
 
-    return {"total_docs": total_docs, "total_chunks": total_chunks}
+    return {"total_docs": total_docs, "total_chunks": total_chunks}