docs(changelog): cut v0.6.5 — charging UX, persistent lightbar, idle-ladder fixes

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

CHANGELOG.md

@@ -10,6 +10,28 @@ Format follows [Keep a Changelog](https://keepachangelog.com/en/1.1.0/). Version
 
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+## [0.6.5-oled-edition] — 2026-05-23
+
+Charging UX (Status-screen battery ETA + amber lightbar pulse), persistent and screen-sticky lightbar control, and a charging-aware idle power ladder. UF2s attached to [the GitHub release](https://github.com/MarcelineVPQ/DS5Dongle-OLED-Edition/releases/tag/v0.6.5-oled-edition) (built by `.github/workflows/release.yml`).
+
+### Added
+
+- **Charge ETA on the OLED Status screen.** While the DualSense is charging, the battery line shows an estimated time-to-full (`~43m`) to the right of the battery icon. The DS5 only reports battery in 10 % steps over BT (`interrupt_in_data[52]` low nibble, 0–10; high nibble is power-state, 1 = charging), so a smooth countdown is impossible — instead `sample_charge_eta()` times how long each 10 % step takes and extrapolates the remaining steps. It shows `~--m` while calibrating (the first estimate can't appear until one full step has been timed, ~15–20 min after plug-in), then refines on each subsequent notch. The partial step in progress at plug-in is discarded so the first estimate isn't skewed by a half-measured step; a 3-entry moving average smooths the rest. **Li-ion taper correction:** a flat "time-per-step × steps-left" runs optimistic in the constant-voltage tail, so each measured step is normalised to a bulk-equivalent duration (divide out a per-step weight: 1.0× in the bulk region, 1.5× for 80→90 %, 2.2× for 90→100 %) and the remaining steps are re-weighted — keeping the estimate consistent whether the user plugs in near-empty or near-full. Sampled once per frame from `oled_loop` ahead of the idle power-ladder early-returns, so step timing stays correct even while the panel is dimmed/off or the user is on another screen.
+- **Lightbar settings persist across reboot and stick across every screen.** The selected lightbar mode and the four favorite colors are now saved to the config flash sector (new `Config_body` fields `lightbar_mode` + `lb_fav_{r,g,b}[4]`), so a chosen mode/color survives a power cycle. A new **HOST** mode (the default) hands the LED back to the host/game so the dongle doesn't hijack player-indicator LEDs out of the box; on upgrade from ≤0.6.4 the unset field reads as HOST, preserving prior behavior. Mode/favorite edits made on the Lightbar screen are batched into a single flash write when you navigate away (tracked by a dirty flag) to spare flash endurance.
+- **Lightbar pulses amber-orange while charging.** A slow ~4.6 s breathing pulse (base `(255,100,0)`, sine-enveloped from dim to bright via the existing 32-step LUT) shows charging at a glance from any screen. Implemented in the unified `lightbar_service()` (below) as the top-priority owner of the LED, so it overrides the selected mode while charging and reverts to it when unplugged.
+
+### Changed
+
+- **The OLED no longer fully sleeps while the controller is charging.** The idle power ladder is capped at the Dim tier (the low-power breathing dot) instead of advancing to full Off (`cmd(0xAE)`) when `g_charge_eta.charging` is true. The charge-ETA tracker already runs while the panel is off, but users were unplugging the controller to "wake" the dongle — which reset the ETA calibration and restarted the wait-for-the-next-10%-notch. Capping at the dot tier (which draws ~no current) removes the reason to unplug. Normal Active→Dim→Off behavior resumes once charging stops.
+- **A single `lightbar_service()` now owns the controller LED, every frame, on every screen.** Previously the OLED only drove the lightbar via a transient `0x31` packet sent from inside `render_screen_lightbar()` — so the color was only asserted while that screen was open. The service (run from `oled_loop` ahead of the power-ladder early-returns) instead writes the chosen color into the persistent `state[]` block (`SetStateData` `LedRed/Green/Blue`, via new `state_set_led()`), so it rides every outbound host/audio packet, and also actively pushes a `0x31` when audio is idle so animations keep moving. A new `g_lightbar_override` flag gates `state_update()` so the host's `AllowLedColor` writes can't stomp a firmware-chosen mode. During audio the active `0x31` push is suppressed — the `0x36` frames already carry `state[]`'s LED, and slipping a `0x31` between them would intrude on the load-bearing audio path.
+
+### Fixed
+
+- **OLED idle dim/dot tier now actually engages while a controller is connected.** The activity detector hashed `interrupt_in_data[0..9]` with an exact compare, but the analog sticks jitter by ±1 LSB at rest, so the hash changed every few frames and reset the idle timer — meaning the breathing-dot/dim tier only ever kicked in when no controller was paired. Now it mirrors `bt.cpp`'s inactivity heuristic: the stick bytes' rest band `[120,140]` is collapsed to a constant and the volatile counter byte (`idata[6]`) is skipped, so a resting controller reads as idle. Confirmed against a live `/dev/hidraw` capture (only the left-stick X byte was flickering 129↔128).
+- **Lightbar no longer reverts the instant you leave the Lightbar screen.** Root cause: the OLED's `send_lightbar_color()` wrote a one-off `0x31` packet and never touched the persistent `state[]` block, while the host's `0x02` output reports, every audio frame, and reconnect all re-stamp `state[]` (incl. the LED) into the controller. Off the Lightbar screen the OLED stopped pushing, so the next `state[]`-based packet overwrote the color — which is why saved favorites and animated modes (Rainbow/Breathing/Fade) never "stuck." Now that the lightbar is owned through `state[]` with a host override gate (see Changed), the selected mode holds across screens and through active gameplay/audio.
+
+---
+
 ## [0.6.4-oled-edition] — 2026-05-19
 
 Trigger-flow diagnostics (in response to issue #3) + the OLED idle power ladder. UF2s attached to [the GitHub release](https://github.com/MarcelineVPQ/DS5Dongle-OLED-Edition/releases/tag/v0.6.4-oled-edition) (built by `.github/workflows/release.yml`).