refactor!: one way to serve books: the stdio server is gone (D-44)

The owner (2026-10-23): "We should probably just delete the stdio path
altogether. THere's no point in that. And it sitting there unused will
just lead to bitrot. Nuke it?"

Books are served only by the books server (`wanderbooks server`),
reached by agents through the bridge (`wanderbooks mcp --book ID`),
which stays.

Removed: `wanderbooks dev-stdio`, the `ledger-mcp` binary, and
`ledger_mcp::run` (stdio and `--http` over a bare data dir), with all
that only that mode had:
- files the books make coming back inline: `HandedFile.content_base64`
  is gone, and `download` and `expires_at` are always there;
- books with no access log or backups: `books.access_log`,
  `books.backup` and `books.back_up_now` are always offered, by scope;
- the settings file read and reloaded (`legacy_files`), the vault key
  named by a file or `--vault-key-file`, and the books dir's
  key-inside-the-books and git checks (with `paths.rs`);
- `wire.rs` (the bridge frames an agent's lines itself);
- `books.settings`' file fields and `books.start`'s `settings_source`.

`BooksServer` is built one way, from `Served` (a book as the books
server serves it), in production and in the unit tests. An unknown tool
is now a protocol error (mcp-tools.md). Inline file input is unchanged.

Then the owner's three decisions (2026-10-23, the question tool):
(a) `books.import_settings` is removed entirely (118 tools): old books
come in whole by `wanderbooks books adopt`, which reads their settings
file once; ledger-config keeps its settings-file parsing only as far as
adoption uses it (`load` and the path-reading `effective_receipt_policy`
are gone), and `books.chart_template` gives its settings as
`books.set_setting` changes. (b) The viewer's loose-books-folder mode is
removed (`--data-dir`, `--books-toml`, `--vault-key-file`, the settings
file and config.json followed): it opens only books of the data root,
reading settings from the journal and the vault from the book's own
`vault/` and `keys/`. (c) `wanderbooks dev-stdio` has no stub: it is an
unknown command like any other word. Also: an upload's expiry past the
calendar is an error, never an empty string.

Tests: every suite that drove the stdio server moved to
crates/ledger-cli/tests/ and drives a real `wanderbooks server` on a
data root of its own (tests/common), handed files by their download;
mcp_stdio.rs is mcp_journeys.rs. Tests of what is gone are deleted and
listed in docs/testing.md. Docs: plan D-44 (D-18 superseded), STATUS,
testing, rules, mcp-interface, the handbook, README; justfile recipes.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01T3gXMVt7XJPi6ens1or9Dj

crates/ledger-gui/tests/tin_copy.rs

@@ -21,7 +21,7 @@ use ledger_gui::nav::Route;
 use ledger_gui::{App, Source, data};
 use ledger_store::Store;
 use ledger_vault::{Tin, Vault};
-use std::path::{Path, PathBuf};
+use std::path::PathBuf;
 
 const SSN: &str = "123-45-6789";
 
@@ -38,17 +38,19 @@ impl Drop for Fixture {
     }
 }
 
-/// Books with one member whose SSN is in the vault; the key lives outside
-/// the books dir, as the server requires.
+/// Books with one member whose SSN is in the vault, the vault and its key
+/// where a book of the data root keeps them (its own `vault/` and
+/// `keys/`).
 fn fixture(tag: &str) -> Fixture {
     let root = std::env::temp_dir().join(format!("ledger-gui-tin-{tag}-{}", std::process::id()));
     let _ = std::fs::remove_dir_all(&root);
     let books = root.join("books");
-    let key = root.join("keys/vault.key");
-    std::fs::create_dir_all(&books).unwrap();
-    let mut s = Store::create(&books.join("books-data"), ledger_core::Currency::USD).unwrap();
+    let key = books
+        .join(ledger_store::root::KEYS_DIR)
+        .join(ledger_store::root::LEGACY_KEY_FILE);
+    let mut s = Store::create(&books, ledger_core::Currency::USD).unwrap();
     let party = s.add_party("Pat Lee", &[Role::Member]).unwrap();
-    let v = Vault::open(&books.join("vault"), &key, true).unwrap();
+    let v = Vault::open(&books.join(ledger_store::root::VAULT_DIR), &key, true).unwrap();
     let hash = v
         .put_tin(party, &Tin::new(SSN, ledger_vault::TinType::Ssn).unwrap())
         .unwrap();
@@ -70,14 +72,12 @@ fn fixture(tag: &str) -> Fixture {
     }
 }
 
-fn load(f: &Fixture, key: Option<&Path>) -> Books {
-    let mut b = data::load_once(&Source {
-        data_dir: f.books.join("books-data"),
+fn load(f: &Fixture) -> Books {
+    data::load_once(&Source {
+        data_dir: f.books.clone(),
         today: Some(chrono::NaiveDate::from_ymd_opt(2026, 10, 16).unwrap()),
     })
-    .unwrap();
-    b.settings.vault_key_file = key.map(Path::to_path_buf);
-    b
+    .unwrap()
 }
 
 fn copied(h: &Harness<'_, App>) -> Vec<String> {
@@ -102,7 +102,7 @@ fn no_digits(s: &str) {
 #[test]
 fn reads_the_vault_with_the_key_in_force() {
     let f = fixture("read");
-    let b = load(&f, Some(&f.key));
+    let b = load(&f);
     assert_eq!(b.tin_from_vault(f.party).unwrap(), SSN);
     let e = b.tin_from_vault(f.party + 1).unwrap_err();
     assert!(e.contains("Not in the vault"), "{e}");
@@ -112,22 +112,12 @@ fn reads_the_vault_with_the_key_in_force() {
 #[test]
 fn a_missing_key_is_locked_and_never_created() {
     let f = fixture("locked");
-    let gone = f.root.join("elsewhere/vault.key");
-    let b = load(&f, Some(&gone));
+    std::fs::remove_file(&f.key).unwrap();
+    let b = load(&f);
     let e = b.tin_from_vault(f.party).unwrap_err();
     assert!(e.contains("locked"), "{e}");
     no_digits(&e);
-    assert!(!gone.exists(), "reading must never create a key");
-}
-
-/// INVARIANT 3: a key file inside the books dir is refused.
-#[test]
-fn a_key_inside_the_books_is_refused() {
-    let f = fixture("inside");
-    let inside = f.books.join("vault.key");
-    std::fs::copy(&f.key, &inside).unwrap();
-    let e = load(&f, Some(&inside)).tin_from_vault(f.party).unwrap_err();
-    assert!(e.contains("inside the books folder"), "{e}");
+    assert!(!f.key.exists(), "reading must never create a key");
 }
 
 /// INVARIANT 4: a tampered record is unreadable, and says nothing of it.
@@ -139,7 +129,7 @@ fn a_bad_record_is_an_error_without_digits() {
     let last = raw.len() - 1;
     raw[last] ^= 1;
     std::fs::write(&rec, raw).unwrap();
-    let e = load(&f, Some(&f.key)).tin_from_vault(f.party).unwrap_err();
+    let e = load(&f).tin_from_vault(f.party).unwrap_err();
     no_digits(&e);
 }
 
@@ -156,7 +146,7 @@ fn party_page(b: Books, party: PartyId) -> Harness<'static, App> {
 fn clicking_the_masked_tin_copies_the_full_number() {
     let f = fixture("click");
     let shown = "TIN on file ••••6789 (SSN)";
-    let mut h = party_page(load(&f, Some(&f.key)), f.party);
+    let mut h = party_page(load(&f), f.party);
     assert!(
         h.query_by_label_contains("12345").is_none(),
         "the full number is never drawn"
@@ -168,8 +158,8 @@ fn clicking_the_masked_tin_copies_the_full_number() {
     assert!(h.query_by_label_contains("12345").is_none());
 
     // Locked: nothing copied; the reason shows beside it.
-    let gone = f.root.join("elsewhere/vault.key");
-    let mut h = party_page(load(&f, Some(&gone)), f.party);
+    std::fs::remove_file(&f.key).unwrap();
+    let mut h = party_page(load(&f), f.party);
     h.get_by_label(shown).click();
     h.step();
     assert!(copied(&h).is_empty());