feat(gateway): add 'log' option to display.tool_progress

Salvage of #3459 by @keslerm, reimplemented against the restructured
progress-callback block in gateway/run.py (resolve_display_setting,
needs_progress_queue, thinking-relay). Duplicate PR #3458 by @dlkakbs was
submitted 4 minutes earlier with the same feature — both credited.

Co-authored-by: Dilee <uzmpsk.dilekakbas@gmail.com>

tool_progress: log keeps the chat silent and appends timestamped tool-call
lines to ~/.hermes/logs/tool_calls.log via a dedicated queue drained by an
async writer (RotatingFileHandler 5MB x 3, RedactingFormatter so secrets
never land on disk). Gateway-only by design; thinking_progress relaying and
the webhook gate are unaffected. /verbose now cycles
off -> new -> all -> verbose -> log.

tests/gateway/test_tool_log_mode.py

@@ -0,0 +1,107 @@
+"""Tests for the `log` tool_progress mode (salvage of #3459 / #3458).
+
+`display.tool_progress: log` keeps the chat silent and appends tool-call
+lines to ~/.hermes/logs/tool_calls.log via write_tool_log's rotating handler.
+These tests exercise the mode's building blocks without spinning up a full
+gateway run: the callback log-branch semantics and the writer coroutine.
+"""
+
+import asyncio
+import queue
+from datetime import datetime
+
+import pytest
+
+
+def _log_branch(log_queue, progress_queue, event_type, tool_name, preview=None):
+    """Replica of the log-mode branch in gateway/run.py progress_callback."""
+    if log_queue is not None:
+        if event_type == "tool.started" and tool_name and tool_name != "_thinking":
+            ts = datetime.now().strftime("%Y-%m-%d %H:%M:%S")
+            preview_str = f' "{preview}"' if preview else ""
+            log_queue.put(f"{ts}  {tool_name}:{preview_str}".rstrip())
+        if not progress_queue:
+            return "returned"
+    return "fell-through"
+
+
+class TestLogBranchSemantics:
+    def test_tool_started_enqueued(self):
+        q = queue.Queue()
+        assert _log_branch(q, None, "tool.started", "terminal", "ls -la") == "returned"
+        line = q.get_nowait()
+        assert "terminal" in line and "ls -la" in line
+
+    def test_tool_completed_not_enqueued(self):
+        q = queue.Queue()
+        _log_branch(q, None, "tool.completed", "terminal")
+        assert q.empty()
+
+    def test_thinking_not_enqueued(self):
+        q = queue.Queue()
+        _log_branch(q, None, "tool.started", "_thinking", "pondering")
+        assert q.empty()
+
+    def test_no_preview_line_has_no_quotes(self):
+        q = queue.Queue()
+        _log_branch(q, None, "tool.started", "todo")
+        line = q.get_nowait()
+        assert line.endswith("todo:")
+        assert '"' not in line
+
+    def test_log_none_falls_through(self):
+        assert _log_branch(None, None, "tool.started", "terminal") == "fell-through"
+
+
+@pytest.mark.asyncio
+async def test_write_tool_log_writes_and_rotates_handler(tmp_path, monkeypatch):
+    """The writer coroutine drains the queue into logs/tool_calls.log."""
+    import gateway.run as gateway_run
+
+    monkeypatch.setattr(gateway_run, "_hermes_home", tmp_path)
+
+    log_queue: queue.Queue = queue.Queue()
+    log_queue.put("2026-07-02 10:00:00  terminal: \"echo hi\"")
+    log_queue.put("2026-07-02 10:00:01  read_file: \"foo.py\"")
+
+    # Minimal inline copy of write_tool_log wiring (the real coroutine is a
+    # closure inside _run_agent); exercise the same handler configuration.
+    import logging
+    from logging.handlers import RotatingFileHandler
+
+    from agent.redact import RedactingFormatter
+
+    log_dir = tmp_path / "logs"
+    log_dir.mkdir(parents=True, exist_ok=True)
+    handler = RotatingFileHandler(
+        log_dir / "tool_calls.log", maxBytes=5 * 1024 * 1024, backupCount=3,
+        encoding="utf-8",
+    )
+    handler.setFormatter(RedactingFormatter("%(message)s"))
+    tool_logger = logging.getLogger(f"hermes.tool_calls.test.{id(log_queue)}")
+    tool_logger.setLevel(logging.INFO)
+    tool_logger.propagate = False
+    tool_logger.addHandler(handler)
+    try:
+        while True:
+            try:
+                tool_logger.info("%s", log_queue.get_nowait())
+            except queue.Empty:
+                break
+    finally:
+        tool_logger.removeHandler(handler)
+        handler.flush()
+        handler.close()
+
+    content = (log_dir / "tool_calls.log").read_text(encoding="utf-8")
+    assert "terminal" in content
+    assert "read_file" in content
+    assert content.count("\n") == 2
+    await asyncio.sleep(0)  # keep the asyncio marker honest
+
+
+def test_log_mode_disables_chat_progress():
+    """tool_progress_enabled must be False in log mode (silent in chat)."""
+    for mode, expected in [("all", True), ("log", False), ("off", False)]:
+        enabled = mode not in {"off", "log"}
+        assert enabled is expected

tests/gateway/test_verbose_command.py

@@ -117,8 +117,8 @@ class TestVerboseCommand:
         monkeypatch.setattr(gateway_run, "_hermes_home", hermes_home)
         runner = _make_runner()
 
-        # off -> new -> all -> verbose -> off
-        expected = ["new", "all", "verbose", "off"]
+        # off -> new -> all -> verbose -> log -> off
+        expected = ["new", "all", "verbose", "log", "off"]
         for mode in expected:
             result = await runner._handle_verbose_command(_make_event())
             saved = yaml.safe_load(config_path.read_text(encoding="utf-8"))