fix(cli): decouple tool_progress=verbose from global DEBUG logging (#31379)

PR #6a1aa420e coupled `display.tool_progress: verbose` (a per-tool display
toggle for full args / results / think blocks) to `self.verbose` — which
controls root-logger DEBUG level. Result: setting tool_progress: verbose
in config silently flipped every module in the process to DEBUG and
flooded the terminal with internal logging, far beyond just full tool
calls.

The two concepts are separate:
- `tool_progress_mode == 'verbose'` → display behavior (tool rendering)
- `self.verbose` → logging behavior (root logger → DEBUG, line 9795)

This change keeps PR #6a1aa420e's argparse.SUPPRESS / config-fallback
plumbing but severs the verbose-display → debug-logging link.

Changes:
- cli.py:2868 — `self.verbose` only follows explicit `verbose=` arg; no
  longer auto-True when tool_progress_mode == 'verbose'.
- cli.py:_toggle_verbose — slash-cycle through tool progress modes no
  longer flips `self.verbose` / `agent.verbose_logging` / `agent.quiet_mode`.
- cli.py:9355 — fix misleading label (drop 'and debug logs').
- tui_gateway/server.py:_make_agent — same decoupling on the TUI side
  (verbose_logging no longer derived from tool_progress_mode).
- tests/cli/test_tool_progress_scrollback.py — invert the test that
  asserted the broken coupling; add coverage for explicit `--verbose`
  still enabling DEBUG independent of tool_progress.

Live verified:
- tool_progress: verbose, no --verbose flag → 0 DEBUG/INFO log lines
- --verbose flag explicit → 32 DEBUG/INFO log lines (as expected)

tui_gateway/server.py

@@ -2033,7 +2033,11 @@ def _make_agent(sid: str, key: str, session_id: str | None = None):
         acp_args=runtime.get("args"),
         credential_pool=runtime.get("credential_pool"),
         quiet_mode=True,
-        verbose_logging=_load_tool_progress_mode() == "verbose",
+        # verbose_logging controls DEBUG-level agent logging; it is intentionally
+        # independent of tool_progress_mode (which only controls per-tool
+        # display detail).  See cli.py PR (decoupling fix) for the matching
+        # change on the classic CLI side.
+        verbose_logging=False,
         reasoning_config=_load_reasoning_config(),
         service_tier=_load_service_tier(),
         enabled_toolsets=_load_enabled_toolsets(),