feat(terminal,cli): docker_extra_args + display.timestamps

Two independent opt-in QoL toggles, both off by default.

terminal.docker_extra_args:
- List of extra flags appended verbatim to docker run after security
  defaults. Useful for adding capabilities (e.g. --cap-add SETUID) or
  other docker run options not exposed by existing config keys.
- Non-string entries are logged and skipped.
- Also available via TERMINAL_DOCKER_EXTRA_ARGS='[...]' env var.

display.timestamps:
- Appends [HH:MM] to user input bullet and the assistant response box
  header. Single hub in _format_submitted_user_message_preview()
  covers both single-line and multi-line user previews; assistant
  response label gets the timestamp at box-open time.

Closes #1569 (timestamps).

Co-authored-by: Mibayy <Mibayy@users.noreply.github.com>

hermes_cli/config.py

@@ -579,6 +579,7 @@ DEFAULT_CONFIG = {
         # Explicit opt-in: mount the host cwd into /workspace for Docker sessions.
         # Default off because passing host directories into a sandbox weakens isolation.
         "docker_mount_cwd_to_workspace": False,
+        "docker_extra_args": [],        # Extra flags passed verbatim to docker run
         # Explicit opt-in: run the Docker container as the host user's uid:gid
         # (via `--user`).  When enabled, files written into bind-mounted dirs
         # (docker_volumes, the persistent workspace, or the auto-mounted cwd)
@@ -901,6 +902,7 @@ DEFAULT_CONFIG = {
         "bell_on_complete": False,
         "show_reasoning": False,
         "streaming": False,
+        "timestamps": False,      # Show [HH:MM] on user and assistant labels
         "final_response_markdown": "strip",  # render | strip | raw
         # Preserve recent classic CLI output across Ctrl+L, /redraw, and
         # terminal resize full-screen clears. Disable if a terminal emulator