feat(notion-search): add Notion search execution with workspace/DB modes

For each expanded query variant: hit Notion's workspace search OR
per-database data_sources.query (when --databases is specified).
Union and dedupe by page ID, cap at 30 candidates total. Filters out
non-page objects (databases) from workspace search results.
Property filters (--filter JSON) pass through to data_sources.query
when in per-database mode.

5 tests: workspace dedup, 30-cap, DB-mode dispatch, page-only filter,
property-filter passthrough. 17 passing total.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

custom-skills/31-notion-organizer/code/scripts/notion_search.py

@@ -11,8 +11,9 @@ from __future__ import annotations
 import json
 import re
 import sys
-from typing import Callable, List, Optional
+from typing import Callable, Dict, List, Optional
 
+import _notion_compat as compat
 from _search_llm import call_claude as default_llm_caller
 
 EXPAND_PROMPT = """You are a query expander for a Notion semantic search tool. Generate up to {n} variants of the user's query that capture related concepts, synonyms, and cross-language alternates (especially Korean ↔ English).
@@ -78,3 +79,60 @@ def expand_query(
         if len(result) >= max_variants:
             break
     return result
+
+
+MAX_CANDIDATES = 30
+
+
+def search_candidates(
+    notion,
+    queries: List[str],
+    *,
+    databases: Optional[List[str]] = None,
+    prop_filter: Optional[Dict] = None,
+) -> List[Dict]:
+    """Run each query against Notion (workspace or per-DB), dedupe, cap at MAX_CANDIDATES.
+
+    Returns a list of page result objects (whatever Notion returned), order preserves
+    first-seen position across all variants — used as fallback ordering when rerank is off.
+    """
+    seen_ids = set()
+    candidates: List[Dict] = []
+
+    for query in queries:
+        if databases:
+            # Per-database query (data_sources.query)
+            for db_id in databases:
+                try:
+                    data_source_id = compat.resolve_data_source_id(notion, db_id)
+                except Exception as exc:
+                    print(f"Warning: could not resolve database {db_id}: {exc}",
+                          file=sys.stderr)
+                    continue
+
+                params = {"data_source_id": data_source_id, "page_size": 100}
+                if prop_filter:
+                    params["filter"] = prop_filter
+
+                response = notion.data_sources.query(**params)
+                for page in response.get("results", []):
+                    page_id = page.get("id")
+                    if page_id and page_id not in seen_ids:
+                        seen_ids.add(page_id)
+                        candidates.append(page)
+                        if len(candidates) >= MAX_CANDIDATES:
+                            return candidates
+        else:
+            # Workspace-wide search
+            response = notion.search(query=query, page_size=100)
+            for item in response.get("results", []):
+                if item.get("object") != "page":
+                    continue
+                page_id = item.get("id")
+                if page_id and page_id not in seen_ids:
+                    seen_ids.add(page_id)
+                    candidates.append(item)
+                    if len(candidates) >= MAX_CANDIDATES:
+                        return candidates
+
+    return candidates