Merge branch 'main' into fix/director-goto-shot

# Conflicts:
#	CHANGELOG.md

docs/CURRENT-STATE.md

@@ -3230,6 +3230,39 @@ test:track` 43 tracking invariants · headless QA harnesses under
 > attribution 18/18). New modules: `src/data/{motionModel,aircraftMeta,aircraftClass,aircraftIcons,issPass,routePlausible,dataCredits}.js`.
 > The live runtime now declares 30 voice tools; the 17→20 count above is retained only as milestone history.
 
+### Interface localization (October 2026)
+
+Shipped locales: **en** (source and fallback), **es** and **ru**. The code lives in
+`src/i18n/`. How to mark UI text: [`docs/I18N.md`](./I18N.md); translator workflow:
+[`docs/TRANSLATORS.md`](./TRANSLATORS.md).
+
+- **Keys are the English text.** `t('Save keys')`, `tn(count, '{count} camera',
+  '{count} cameras')`, and `msg('Live Flights')` for text stored in data and
+  translated later. Markup opts in with `data-i18n` (element text) and
+  `data-i18n-title` / `-aria-label` / `-placeholder` (that attribute's English
+  value). English has no catalog; every other locale is
+  `src/i18n/locales/<code>.json`, and a missing entry falls back to English.
+- **Locale choice.** `?lang=` → stored choice (`gev:locale:v1`) →
+  `navigator.languages` → English. `?lang=` is not stored, and share links drop
+  it, so a recipient keeps their own language. The globe picker in the
+  bottom-right corner (`src/ui/localePicker.js`) stores the choice, drops
+  `?lang=` (keeps it only when storage is blocked) and reloads. It asks first
+  when the reload would lose work registered with `registerUnsavedWork`:
+  unsaved keys or CCTV calibration, Draw marks, imported map files, the open
+  cockpit, a voice session.
+- **Gate.** `npm run i18n` (and `src/i18n/catalog.test.mjs` under `npm test`)
+  extracts every message and fails on missing, empty, unused,
+  placeholder-mismatched, still-English (plural forms included) or
+  wrongly-shaped plural entries.
+- **Not translated by design:** layer ids, share-link and hash parameters, API
+  fields, voice tool schemas, provider names, feed data (callsigns, vessel and
+  station names) and attribution.
+- **Unmarked text.** The same check lists UI text that is not marked at all
+  (markup without `data-i18n*`, literals reaching the page without `t`/`tn`/`msg`)
+  and fails on it. Text kept on purpose says why: `translate="no"`,
+  `data-i18n-runtime`, or `// i18n-ignore: <reason>`. `src/tools/` is skipped:
+  it writes for AI clients, not the page.
+
 ## Canonical Docs Order
 
 Use docs in this order when details conflict:
@@ -5398,6 +5431,22 @@ Local FM and internet radio are one listening surface: starting local FM stops
 internet-radio playback, and starting internet radio stops local FM. ADS-B
 reception does not interrupt internet radio.
 
+- **FM seek.** Seeking wraps across 87.5–108 MHz, covers both band edges and
+  skips the starting station. Spectra carry a decoder epoch, so a retune or mode
+  change rejects earlier output. A failed scan retune stops seeking. This
+  integrates Aditya's (@Rohilalala) contribution in #1174; it does not change
+  the peak-selection algorithm or guarantee that a final station retune succeeds.
+- **Streaming and playback.** Four ordered USB reads keep input available while
+  the page handles other work; control changes drain those reads before touching
+  the receiver. The worker must finish loading before reads start. Decoder work
+  is limited to eight unacknowledged blocks / 512 KiB, with a one-second oldest
+  block watchdog. Overload stops the receiver with an explicit error. Stop
+  terminates the worker immediately and disables the audio session; stale decoder
+  output and audio from retired sessions are refused. FM audio starts after an
+  80 ms prebuffer and retains at most 256 ms, dropping the oldest frames on
+  overflow. FM signal display updates are coalesced to at most four per second;
+  spectra are computed only while seeking. Optional `decoderDiagnostics` adds
+  bounded timing samples and overload snapshots without recording audio or IQ.
 - **Modes.** FM (87.5–108 MHz, tune, seek, volume) or ADS-B at 1090 MHz.
   With a receiver open, selecting ADS-B enables the Local ADS-B layer;
   selecting FM disables it.