feat(cli): add SQLite cache, shared solution runner, and submit command

apps/cli/submit.ts

@@ -0,0 +1,7 @@
+#!/usr/bin/env bun
+/**
+ * Fuzzy-select a solution file from work/ and submit it to LeetCode's judge.
+ */
+import { runOnSolution } from "./solutions";
+
+await runOnSolution("submit", "Submit which solution?");