Plan M5a: local memory in 15 tasks

memoryd (files, the check, edits, journal, index, recall, serving),
the memory tools and built-in grants in brokerd, the memory block in
loopd, bxctl reindex and memory, and the device checks with memoryd.

Each task was built as a reference and gated. Each was replayed on its
own at its end state (854 to 936 tests) and mutation-checked. Each
skeleton compiles and fails its tests. Every todo comment was read
beside its signature.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

docs/plans/M5a/files/crates/memoryd/tests/entries.rs

@@ -0,0 +1,45 @@
+//! Entries: split at `§` lines, rendered back, and measured in characters (M5a spec, section 3).
+//! Do not edit.
+
+use memoryd::entries::{parse, render, size};
+
+fn owned(entries: &[&str]) -> Vec<String> {
+    entries.iter().map(|e| e.to_string()).collect()
+}
+
+#[test]
+fn parse_splits_at_separator_lines_and_trims() {
+    assert_eq!(parse(""), Vec::<String>::new());
+    assert_eq!(parse("\n\n"), Vec::<String>::new());
+    assert_eq!(parse("one"), owned(&["one"]));
+    assert_eq!(
+        parse("one\n§\ntwo\nlines\n  §  \n\n three \n§\n§\n"),
+        owned(&["one", "two\nlines", "three"])
+    );
+    assert_eq!(
+        parse("a § b\n§\nc"),
+        owned(&["a § b", "c"]),
+        "§ inside a line is text"
+    );
+}
+
+#[test]
+fn render_is_what_parse_reads() {
+    let entries = owned(&["Owner prefers UTC.", "Works on\nboxmaker."]);
+    let text = render(&entries);
+    assert_eq!(text, "Owner prefers UTC.\n§\nWorks on\nboxmaker.\n");
+    assert_eq!(parse(&text), entries);
+    assert_eq!(render(&[]), "");
+}
+
+#[test]
+fn size_counts_characters_with_separators() {
+    assert_eq!(size(&[]), 0);
+    assert_eq!(size(&owned(&["abc"])), 3);
+    assert_eq!(
+        size(&owned(&["abc", "de"])),
+        3 + 3 + 2,
+        "a separator line is \\n§\\n"
+    );
+    assert_eq!(size(&owned(&["ééé"])), 3, "characters, not bytes");
+}