Refine chat controls and add explicit owner recovery reset

Simplify the ASCII interface, expose owner setup, and load any selected number of messages using bounded history batches. Add backend-only owner reset with a matching public fingerprint and stopped-service guards, and document the loss of old history and key continuity.

1 files changed, 22 insertions, 2 deletions

diff --git a/crates/chat-server/src/main.rs b/crates/chat-server/src/main.rs
index 6c7f4e1..c17a7f6 100644
--- a/crates/chat-server/src/main.rs
+++ b/crates/chat-server/src/main.rs
@@ -16,6 +16,7 @@
 #![doc = "Local experimental chat server with ciphertext-only durable storage."]
 
 mod http;
+mod maintenance;
 mod service;
 mod store;
 
@@ -33,8 +34,16 @@ struct Arguments {
     root: PathBuf,
     #[arg(long, default_value = "127.0.0.1:9080")]
     bind: SocketAddr,
-    #[arg(long)]
+    #[arg(long, conflicts_with_all = ["reset_owner", "owner_fingerprint", "snapshot"])]
     init: bool,
+    #[arg(long, value_name = "FINGERPRINT", conflicts_with_all = ["owner_fingerprint", "snapshot"], help = "Permanently clear the matching owner registration and all chat history after key loss")]
+    reset_owner: Option<String>,
+    #[arg(
+        long,
+        conflicts_with = "snapshot",
+        help = "Print the registered owner's public fingerprint"
+    )]
+    owner_fingerprint: bool,
     #[arg(long)]
     snapshot: Option<PathBuf>,
 }
@@ -76,11 +85,22 @@ async fn run(arguments: Arguments) -> Result<()> {
     std::fs::create_dir_all(&data)?;
     std::fs::set_permissions(&data, std::os::unix::fs::PermissionsExt::from_mode(0o700))?;
     let database = data.join("chat.sqlite");
-    let store = store::Store::open(&database)?;
+    let _server_lock = if arguments.snapshot.is_none() && !arguments.owner_fingerprint {
+        Some(maintenance::lock(&data)?)
+    } else {
+        None
+    };
+    let mut store = store::Store::open(&database)?;
     std::fs::set_permissions(
         &database,
         std::os::unix::fs::PermissionsExt::from_mode(0o600),
     )?;
+    if arguments.owner_fingerprint {
+        return maintenance::fingerprint(&store);
+    }
+    if let Some(expected) = arguments.reset_owner {
+        return maintenance::reset(&mut store, &expected, arguments.bind);
+    }
     if let Some(destination) = arguments.snapshot {
         store.snapshot(&destination)?;
         std::fs::set_permissions(