feat(cli): chat — Tier 2 check on the signing device, interactive room

Each message's signing device is checked against the group's roster as the
page checks it (a port of transport-roster.js, held to it by the parity
test): chains of countersignatures walked from each account's roots, the
keys accepted per account and node kept in the store, the roster read again
once before a key is called changed. Only "changed" is said, under the
message; --json carries every verdict.

chat with no group opens the interactive chat: the groups, then one group's
conversation IRC-style with pushed messages arriving live and a line to
write in; Esc or /part goes back to the groups, /quit or Ctrl+Q quits. Like
the bare command, it opens on the sign-in screen when nothing is stored.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

1 files changed, 9 insertions, 6 deletions

diff --git a/packages/meshbay-cli/src/meshbay_cli/tui/app.py b/packages/meshbay-cli/src/meshbay_cli/tui/app.py
index dbb773c..fe7fa2c 100644
--- a/packages/meshbay-cli/src/meshbay_cli/tui/app.py
+++ b/packages/meshbay-cli/src/meshbay_cli/tui/app.py
@@ -3,7 +3,8 @@
 
 Textual, because it runs on the same asyncio loop as aiortc and httpx rather
 than beside them, and on Linux terminals and Windows' consoles alike. Signed in
-already, it opens on the two panes; otherwise on the sign-in screen first.
+already, it opens on the two panes — or, for `meshbay-cli chat` with no group,
+on the groups to chat in (`tui/chat.py`); otherwise on the sign-in screen first.
 
 Nothing is printed while it runs — a line on stderr would tear the screen — so
 the log goes to a file in the CLI's data directory instead.
@@ -24,10 +25,12 @@ from .screens import DeviceCode, MainScreen, SignInScreen
 class MeshBayApp(App):
     TITLE = "MeshBay"
 
-    def __init__(self, ctx: Context):
+    def __init__(self, ctx: Context, home=MainScreen):
         super().__init__()
         self.ctx = ctx
         self.hub = ctx.hub
+        # The screen a signed-in account lands on, made from the account.
+        self.home = home
 
     async def use_hub(self, url: str) -> None:
         if url != self.hub.url:
@@ -51,9 +54,9 @@ class MeshBayApp(App):
     def start(self, account: Account) -> None:
         account.on_device_code = DeviceCode(self)
         if isinstance(self.screen, SignInScreen):
-            self.switch_screen(MainScreen(account))
+            self.switch_screen(self.home(account))
         else:
-            self.push_screen(MainScreen(account))
+            self.push_screen(self.home(account))
 
 
 def _log_to_file() -> None:
@@ -70,7 +73,7 @@ def _log_to_file() -> None:
     root.addHandler(handler)
 
 
-async def run_interactive(ctx: Context) -> int:
+async def run_interactive(ctx: Context, home=MainScreen) -> int:
     _log_to_file()
-    await MeshBayApp(ctx).run_async()
+    await MeshBayApp(ctx, home).run_async()
     return 0