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.

locales/en.yaml

@@ -379,6 +379,7 @@ gateway:
     mode_new:              "⚙️ Tool progress: **NEW** — shown when tool changes (preview length: `display.tool_preview_length`, default 40)."
     mode_all:              "⚙️ Tool progress: **ALL** — every tool call shown (preview length: `display.tool_preview_length`, default 40)."
     mode_verbose:          "⚙️ Tool progress: **VERBOSE** — every tool call with full arguments."
+    mode_log:              "⚙️ Tool progress: **LOG** — silent in chat; tool calls written to ~/.hermes/logs/tool_calls.log."
     saved_suffix:          "_(saved for **{platform}** — takes effect on next message)_"
     save_failed:           "_(could not save to config: {error})_"