feat(oled): misc-fixed 6x9 font on SSD1306 too, for GAT562 30S solo

The misc-fixed font (full Latin/Greek/Cyrillic) had only ever reached
SH1106Display and the e-ink driver. GAT562 30S -- like 24 other variants
-- uses SSD1306Display, which stayed on the built-in 5x7 font, so every
keyboard alphabet beyond ASCII and every accented contact name was
transliterated (Łódź -> Lodz) or drawn as a filled block.

Extract the renderer into MiscFixedRenderer.h rather than copying it:
Adafruit_SH110X and Adafruit_SSD1306 both derive from Adafruit_GFX and
glyph drawing is pure pixel plotting, so one implementation serves both
drivers (-79 lines from SH1106Display.cpp, same flash usage as before).
The header is .cpp-only by contract -- the font tables are static const,
so including it from a driver header would land a copy in every
translation unit.

On SSD1306 the path is opt-in behind OLED_MISC_FIXED_FONT, set only in
the two GAT562 30S solo envs: the font costs ~14 KB of flash and the
other 24 variants' repeater/companion builds have no keyboard to type
those alphabets on. Without the flag that driver is unchanged, verified
by building GAT562_30S_Mesh_Kit_repeater.

Drive-by consistency fix from the extraction: a newline in print() now
advances the cursor by yAdvance * text_size instead of a single yAdvance,
which was half a row short at setTextSize(2). The e-ink driver always
scaled it. No effect at size 1, which is everywhere the UI prints '\n'.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

release-notes.md

@@ -8,6 +8,7 @@
 - **Bot Trigger fields accept multiple phrases.** Pack several trigger words into one Trigger field, comma-separated (`hi,hello there,yo`) — matching any one of them fires the reply, same as before for a single phrase.
 - **Remote Bot Actions gain `!gpio1`..`!gpio4`** (Wio Tracker L1 only — 4 otherwise-unused pins). Each pin is independently set to Off/Input/Output (GPIO1/GPIO2 also offer Analog) from a new **Tools › GPIO** screen; `!gpio1 on`/`!gpio1 off` drives an Output pin remotely, a bare `!gpio1` reports the current mode and reading (including a millivolt value in Analog mode). Gated by the same per-target Actions toggle as `!buzz`/`!gps`/`!advert`.
 - **Optional CardKB support (Wio Tracker L1, Grove I2C) — full keyboard-only navigation.** Plug an M5Stack CardKB into the Grove connector and it's auto-detected at boot — no setting to flip. Typing goes straight into the message/name field instead of navigating the on-screen keyboard grid, always as plain Latin text regardless of the Settings › Keyboard language/type — arrows and Esc work as expected everywhere else too (including inside the placeholder and accent popups). Enter acts like the physical centre button (advances the on-screen grid selection) rather than submitting, so **Fn+Enter** sends the message/confirms the field from anywhere, and **Fn+`<letter>`** opens that letter's accent popup directly (no arrow-hunting needed — handy for Polish/Czech/etc. diacritics — and works no matter what language/keyboard type is configured, since CardKB always types Latin either way). **Tab** is the Hold-Enter equivalent everywhere, including message reply/navigate and the Bot/Admin/Repeater menus — same single shortcut whether or not the on-screen keyboard is showing.
+- **GAT562 30S solo builds now use the same OLED font as the Wio Tracker L1.** The misc-fixed 6x9 font (full Latin, Greek and Cyrillic) had only ever reached the SH1106 and e-ink drivers, so on this board every keyboard alphabet beyond ASCII, and every accented contact name, was still being transliterated (`Łódź` → `Lodz`) or drawn as a filled block. Solo builds only — the font costs ~14 KB of flash and the repeater/companion builds have no keyboard to type those alphabets on; they keep the built-in font and are byte-for-byte unchanged.
 - **Settings › Keyboard gets an "Ext. KB" row** (boards that support CardKB, above). Switching it to **Compact** hides the on-screen letter grid, special-row icons, and status line entirely — a CardKB typist never looks at any of it, and none of it (script/page, T9-vs-ABC, caps) is actually actionable from CardKB anyway — replacing them with just a reminder of the Tab/Fn+letter shortcuts; the accent and placeholder popups still show normally. With the grid hidden, arrows and Tab take on more useful direct meanings instead of driving an invisible grid selection: **arrows** move the text cursor immediately (no more entering cursor mode first), **plain Enter** submits the message/field (same as Fn+Enter — there's no grid cell to commit), and **plain Tab** opens the placeholder picker directly. Compact is designed to need no joystick/physical button at all, and reclaims the freed space for extra message-preview lines. Off (**Full**) by default.
 
 ### Fixes