core/cli: show context char estimate in /status

Surface soft budget usage (context_chars and tool_result_max) for
Phase D without introducing a local tokenizer.

src/plyngent/cli/repl.py

@@ -54,14 +54,20 @@ _CONTENT_PREVIEW = 200
 
 
 def _cmd_status(state: ReplState) -> None:
+    from plyngent.agent.budget import estimate_messages_chars
+
     pending = state.agent.pending_retry_text
     pending_disp = "yes" if pending else "no"
+    ctx_chars = estimate_messages_chars(state.agent.messages)
+    ctx_budget = state.agent.max_context_chars
     click.echo(
         f"provider={state.provider_name}  model={state.model}\n"
         f"session={state.session_id}  messages={len(state.agent.messages)}  "
         f"pending_retry={pending_disp}\n"
         f"tools={'on' if state.tools_enabled else 'off'}  "
         f"rounds={state.max_rounds}  stream={'on' if state.agent.stream else 'off'}\n"
+        f"context_chars={ctx_chars}/{ctx_budget}  "
+        f"tool_result_max={state.agent.max_tool_result_chars}\n"
         f"workspace={state.workspace}"
     )
 

tests/test_cli/test_repl_commands.py

@@ -140,3 +140,16 @@ async def test_rounds(state: ReplState) -> None:
     assert await handle_slash(state, "/rounds 40") is True
     assert state.max_rounds == 40  # noqa: PLR2004
     assert state.agent.max_rounds == 40  # noqa: PLR2004
+
+
+async def test_status_shows_context_chars(
+    state: ReplState, capsys: pytest.CaptureFixture[str]
+) -> None:
+    from plyngent.lmproto.openai_compatible.model import UserChatMessage
+
+    state.agent.messages = [UserChatMessage(content="hello")]
+    assert await handle_slash(state, "/status") is True
+    out = capsys.readouterr().out
+    assert "context_chars=" in out
+    assert "tool_result_max=" in out
+    assert str(state.workspace) in out