refactor(reader): extract.rs moves into ledger-reader (U0d)

D-61 (Q-9): the writer sheds the typesetter and the crate map is layered
again. The PDF/XLSX reader (extract.rs, plan P6) is now the plain library
crate ledger-reader, moved whole with git mv and no behavior change.
ledger-store depends on it instead of ledger-import, so the store no
longer builds Typst or the fonts; ledger-import re-exports it as
ledger_import::extract so gui, mcp, host and the fuzz targets compile
unchanged, and still never depends on the store. New crate carries only
the dependencies extract.rs imports (hayro, hayro-interpret, kurbo, zip,
quick-xml, thiserror); fuzz/Cargo.lock gains the new package.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HS8WZziDnyxunC23MUxrLp

crates/ledger-store/Cargo.toml

@@ -8,11 +8,11 @@ description = "Durable persistence for wanderbooks: a hash-chained JSONL journal
 
 [dependencies]
 ledger-core = { path = "../ledger-core" }
-# The one extractor (plan P6 step 1, D-53): the writer journals a file's
+# The one reader (plan P6 step 1, D-53, D-61: its own crate): the writer journals a file's
 # text at attach time and on `wanderbooks books extract`, so the extractor
 # must be callable here rather than only from the server. It is pure and
 # deterministic (no I/O, no network, no time source).
-ledger-import = { path = "../ledger-import" }
+ledger-reader = { path = "../ledger-reader" }
 rusqlite = { version = "0.32", features = ["bundled"] }
 serde = { version = "1", features = ["derive"] }
 serde_json = "1"