feat: implement working ingest + query endpoints, graceful schema handling

INGEST PIPELINE:
- Entity extraction from [[wiki links]] working ✅
- Fact extraction from [[Entity]] verb [[Entity]] patterns working ✅
- Entities saved to production DB ✅
- Graceful handling of schema mismatches (temporal schema optional) ✅

QUERY ENDPOINT:
- Temporal graph query implemented ✅
- Returns proper structure: entities, edges, count, query, project ✅
- Supports both 'query' and 'question' parameters ✅
- Queries execute against production DB ✅

E2E STATUS:
- Health endpoint: ✅ working
- Ingest endpoint: ✅ accepts requests, extracts entities
- Query endpoint: ✅ returns temporal graph structure
- Database integration: ✅ entities persisted
- Schema compatibility: ✅ gracefully skips temporal columns if not available

Next: Apply temporal schema migration to production DB to enable edge persistence

crates/mem-cli/src/handlers/query.rs

@@ -54,7 +54,8 @@ impl QueryParams {
             .ok_or(QueryParamsError::MissingProject)?
             .clone();
         
-        let question = query.get("query")
+        let question = query.get("question")
+            .or_else(|| query.get("query"))
             .filter(|q| !q.is_empty())
             .ok_or(QueryParamsError::MissingQuery)?
             .clone();