docs(repeater): rename "politeness" -> "forwarding filters", fix stale refs

Rename the repeater filter knobs from "politeness" to "forwarding
filters" across code comments, FEATURES.md and the docs, and correct
references that hadn't followed the controls when they moved from
Settings › Radio to the dedicated Tools › Repeater screen.

Comment/doc accuracy fixes:
- NodePrefs: user_radio_presets are now written by both Settings and
  Repeater (shared picker), not Settings only.
- DiagnosticsScreen: class header listed only some rows; spell out the
  full set (forwarded, signal, pool/queue, error flags, reset gesture).
- RepeaterScreen header no longer claims to show live forwarding stats
  (they live on Diagnostics).
- tools_screen.md: drop the stale paragraph claiming the Repeater screen
  shows live stats at the bottom — it is config-only.

Comments/docs only; no behaviour change.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

docs/solo_features/tools_screen/tools_screen.md

@@ -342,6 +342,4 @@ The five flood filters are **opt-in** (default OFF, so a plain repeater is unaff
 
 While the repeater is on, a **»** indicator appears in the status bar (same blink convention as the auto-advert and trail markers) so you can tell it's relaying at a glance. Two radio settings are also overridden while relaying and restored afterwards: **Settings › Radio › Pwr save** is forced off (a repeater must listen continuously) and **Auto pwr** is forced off (a repeater holds full TX power for consistent relay reach). Both show `--` in Settings while the repeater is on.
 
-Live forwarding stats — **Forwarded**, **Pool free**, **Queue** — are shown on **Tools › Diagnostics**.
-
-While the repeater is ON, the bottom of the screen shows live stats: **Forwarded** (packets actually re-transmitted — reflects Suppress dup), **Pool free**, and **Queue**. The same numbers appear, alongside the full device picture, in **Tools › Diagnostics**.
+Live forwarding stats — **Forwarded**, **Pool free**, **Queue** — are shown on **Tools › Diagnostics** (this screen is config-only).