fix: resolve compilation errors in mem-ingest and mem-cli

- Fix Record import: mem_core::Record instead of mem_chunk
- Remove unused imports (anyhow::anyhow, Pin, Context, Poll, Result)
- Stub check_database() in verify.rs (pending PgRepo implementation)
- Wrap run_id with Some() to match Option<String> type
- All tests pass, no blocking compilation errors

crates/mem-ingest/src/doc_corpus.rs

@@ -3,7 +3,7 @@
 //! Reads a directory tree of markdown files, splits on ATX headings,
 //! and emits one Record per section with breadcrumb paths attached.
 
-use anyhow::{anyhow, Result};
+use anyhow::Result;
 use mem_chunk::RecordSource;
 use mem_core::{Provenance, Record, Role};
 use futures::stream::{self, Stream};