feat(#2635): consolidate todos + reminders into one hyperhive-state.sqlite

hive-agent/src/paths.rs

@@ -40,19 +40,52 @@ pub fn harness_dir() -> PathBuf {
     hive_sh4re::paths::harness_dir()
 }
 
-/// Harness-local todo store (loose-ends v2). A dedicated sqlite db under
-/// the harness dir — the todos are mutable per-agent state the harness
-/// owns, kept out of the append-only `hyperhive-events.sqlite` sink.
+/// Consolidated harness-local state db — currently todos + reminders, one
+/// table each — mutable per-agent state the harness owns, kept out of the
+/// append-only `hyperhive-events.sqlite` sink. Per mara's call ("not yet
+/// another sqlite! todos, reminders, questions should be like three tiny
+/// tables in one 500kb sqlite"), this file is the shared home for all
+/// loose-ends-v2 stores; each store's `open()` only applies its own
+/// `CREATE TABLE IF NOT EXISTS`, so opening multiple stores against the
+/// same path is safe (distinct table names, no schema collision). A
+/// questions mirror table is the planned third tenant (a following
+/// increment), not part of this schema yet.
+/// [`todos_db`] and [`reminders_db`] both resolve here — kept as separate
+/// fns (rather than every call site reading `state_db` directly) so each
+/// store's callers still say what they mean.
+///
+/// Before this consolidation, todos and reminders lived in their own
+/// `hyperhive-todos.sqlite` / `hyperhive-reminders.sqlite` files; a
+/// one-time boot migration (`db_migrate::run`) folds those into this path
+/// the first time a harness boots after the upgrade.
+#[must_use]
+pub fn state_db() -> PathBuf {
+    harness_dir().join("hyperhive-state.sqlite")
+}
+
+/// Harness-local todo store (loose-ends v2) path — see [`state_db`].
 #[must_use]
 pub fn todos_db() -> PathBuf {
+    state_db()
+}
+
+/// Harness-local reminder store path — see [`state_db`].
+#[must_use]
+pub fn reminders_db() -> PathBuf {
+    state_db()
+}
+
+/// Legacy pre-consolidation todos db path, consulted only by
+/// [`crate::db_migrate`] on the first boot after the upgrade.
+#[must_use]
+pub fn legacy_todos_db() -> PathBuf {
     harness_dir().join("hyperhive-todos.sqlite")
 }
 
-/// Harness-local reminder store. Same rationale as [`todos_db`] — mutable
-/// per-agent state the harness owns, kept out of the append-only events
-/// sink.
+/// Legacy pre-consolidation reminders db path, consulted only by
+/// [`crate::db_migrate`] on the first boot after the upgrade.
 #[must_use]
-pub fn reminders_db() -> PathBuf {
+pub fn legacy_reminders_db() -> PathBuf {
     harness_dir().join("hyperhive-reminders.sqlite")
 }