feat: add persistent dynamic panels

crates/lumbridge-storage/src/lib.rs

@@ -75,6 +75,12 @@ CREATE TABLE IF NOT EXISTS workspace_buzz_channels (
     channel_name TEXT NOT NULL,
     PRIMARY KEY (workspace_id, account_id, channel_id)
 ) STRICT;
+
+CREATE TABLE IF NOT EXISTS workspace_snapshots (
+    workspace_id TEXT PRIMARY KEY NOT NULL,
+    snapshot_json TEXT NOT NULL,
+    updated_at TEXT NOT NULL DEFAULT CURRENT_TIMESTAMP
+) STRICT;
 ";
 
 #[derive(Debug)]
@@ -222,6 +228,44 @@ impl Store {
         .transpose()
     }
 
+    /// Save a credential-free UI snapshot for a workspace.
+    ///
+    /// The caller owns the versioned JSON shape. This storage boundary treats
+    /// it as opaque local state and must never receive secrets or transcripts.
+    ///
+    /// # Errors
+    ///
+    /// Returns an error when `SQLite` cannot insert or update the snapshot.
+    pub fn save_workspace_snapshot(&self, workspace_id: &str, snapshot_json: &str) -> Result<()> {
+        self.connection.execute(
+            r"
+            INSERT INTO workspace_snapshots (workspace_id, snapshot_json)
+            VALUES (?1, ?2)
+            ON CONFLICT(workspace_id) DO UPDATE SET
+                snapshot_json = excluded.snapshot_json,
+                updated_at = CURRENT_TIMESTAMP
+            ",
+            params![workspace_id, snapshot_json],
+        )?;
+        Ok(())
+    }
+
+    /// Load the last credential-free UI snapshot for a workspace.
+    ///
+    /// # Errors
+    ///
+    /// Returns an error when `SQLite` cannot read the snapshot.
+    pub fn workspace_snapshot(&self, workspace_id: &str) -> Result<Option<String>> {
+        self.connection
+            .query_row(
+                "SELECT snapshot_json FROM workspace_snapshots WHERE workspace_id = ?1",
+                [workspace_id],
+                |row| row.get(0),
+            )
+            .optional()
+            .map_err(StorageError::from)
+    }
+
     #[cfg(test)]
     fn contains_column(&self, table: &str, column: &str) -> Result<bool> {
         let mut statement = self
@@ -281,4 +325,23 @@ mod tests {
             );
         }
     }
+
+    #[test]
+    fn workspace_snapshot_round_trips_as_opaque_local_state() {
+        let store = Store::open_in_memory().expect("store should initialize");
+        assert_eq!(store.workspace_snapshot("lumbridge-code").unwrap(), None);
+        store
+            .save_workspace_snapshot(
+                "lumbridge-code",
+                r#"{"selected":7,"panels":[{"id":7,"kind":"terminal"}]}"#,
+            )
+            .unwrap();
+        assert_eq!(
+            store
+                .workspace_snapshot("lumbridge-code")
+                .unwrap()
+                .as_deref(),
+            Some(r#"{"selected":7,"panels":[{"id":7,"kind":"terminal"}]}"#)
+        );
+    }
 }