fix(completion): scoped table lookup, preserve casing, lower Oracle table-function boost

* fix: improve schema-qualified SQL completion

* fix(completion): preserve casing in completion table cache key and relaxed filter

---------

Co-authored-by: zipg <4047349+zipg@users.noreply.github.com>
Co-authored-by: t8y2 <1156263951@qq.com>

apps/desktop/src/lib/__tests__/sql/sqlCompletion.context.spec.ts

@@ -271,4 +271,15 @@ describe("sqlCompletion scoped metadata ranking", () => {
     expect(items.length).toBeLessThanOrEqual(200);
     expect(items[0]?.label).toBe("TempTable_000");
   });
+
+  it("ranks real Oracle tables before built-in table functions in FROM contexts", () => {
+    const sql = "SELECT * FROM ";
+    const items = buildSqlCompletionItems(sql, sql.length, {
+      databaseType: "oracle",
+      tables: [{ name: "ORDERS_10K", schema: "DBX_TEST", type: "table" }],
+      columnsByTable: new Map(),
+    });
+
+    expect(items.findIndex((item) => item.label === "ORDERS_10K")).toBeLessThan(items.findIndex((item) => item.label === "TABLE"));
+  });
 });