docs: architecture map (initial 5-slice generation, 105 pages)

Five-slice navigable map of the entire codebase under
docs/architecture-map/. Each slice is a self-contained
breadcrumbed sub-tree:

  01-frontend (16)              Svelte/SvelteKit UI
  02-tauri-runtime (26)         src-tauri commands + lifecycle
  03-audio-transcription (16)   audio + transcription crates
  04-llm-formatting-mcp (19)    llm, ai-formatting, mcp, cloud
  05-core-storage-hotkey-build  core, storage, hotkey, workspace,
                          (26) CI, dev glue

Plus master README.md and data-flow-end-to-end.md tracing
audio bytes from microphone to FTS5 search to MCP read.

Generated by 5 parallel subagents on 2026/05/09 against
HEAD 3c47000. Each page has YAML frontmatter, file:line code
refs, sibling cross-links, plain-English summaries.

Aggregated debt surfaced (full lists in master README):
RB-08 macOS power assertion, schema head drift v14 vs v15,
VAD blocked on ort version conflict, streaming primitives
not wired into live.rs, no prompt versioning, MCP has no
auth, cloud-providers in-memory keystore, SettingsPage
2 484 LOC, commands/live.rs 1 737 LOC, dual theme system,
brand rename to Lumenote pending across the codebase.

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

docs/architecture-map/01-frontend/i18n.md

@@ -0,0 +1,75 @@
+---
+name: Internationalisation
+type: architecture-map-page
+slice: 01-frontend
+last_verified: 2026/05/09
+---
+
+# Internationalisation
+
+> **Where you are:** [Architecture map](../README.md) → [Frontend](README.md) → Internationalisation
+
+**Plain English summary.** svelte-i18n is wired but coverage is intentionally minimal. The infrastructure (loader, persisted choice, Settings selector) is in place so strings can migrate incrementally. Three locales: English (source of truth), Spanish, German. Most strings still render hardcoded.
+
+## At a glance
+
+- **Path:** `src/lib/i18n/`
+- **LOC:** 73 (`index.ts`) + 19 lines per locale JSON.
+- **Key files:**
+  - `src/lib/i18n/index.ts`. Setup, locale detection, public exports.
+  - `src/lib/i18n/locales/en.json`. 19 lines.
+  - `src/lib/i18n/locales/es.json`. 19 lines.
+  - `src/lib/i18n/locales/de.json`. 19 lines.
+- **Library:** `svelte-i18n` 4.0.1.
+
+## What's in here
+
+### `index.ts`
+
+```ts
+import { init, register, locale as svelteLocale } from "svelte-i18n";
+import { derived, get } from "svelte/store";
+
+export type Locale = "en" | "es" | "de";
+
+export const SUPPORTED_LOCALES: { code: Locale; label: string }[] = [
+  { code: "en", label: "English" },
+  { code: "es", label: "Español" },
+  { code: "de", label: "Deutsch" },
+];
+
+const STORAGE_KEY = "magnotia_locale";
+
+register("en", () => import("./locales/en.json"));
+register("es", () => import("./locales/es.json"));
+register("de", () => import("./locales/de.json"));
+
+function detectInitialLocale(): Locale { /* localStorage → navigator.language → "en" */ }
+```
+
+Public exports:
+- `initI18n()`. Idempotent. Called from every layout's `onMount`-ish path (`+layout.svelte:38` and the float/viewer/preview break layouts).
+- `setLocale(code)`. Writes to `magnotia_locale` and updates the svelte-i18n store.
+- `currentLocale`. A derived store that components subscribe to via `$currentLocale`.
+- `SUPPORTED_LOCALES` constant for the picker.
+
+### Locale JSON shape
+
+19 lines per file means roughly a dozen translated strings. Treat the locales as a stub. Most page text is still hardcoded.
+
+## Where it is consumed
+
+- `SettingsPage.svelte:22` imports `_` (the translation function) and `SUPPORTED_LOCALES`, `setLocale`, `currentLocale`. The locale picker UI lives in Settings.
+- A handful of strings inside SettingsPage use `$_('key')`.
+
+## Watch outs
+
+- Adding a new locale is one `register("xx", () => import("./locales/xx.json"))` call plus a `SUPPORTED_LOCALES` entry.
+- Cross window: each window initialises i18n independently via its layout. Locale change persists to `localStorage["magnotia_locale"]`. Float and viewer pick up the new locale on the next mount, not live. Worth wiring a Tauri event if live cross-window translation is needed.
+- The "British English" toggle in `settings.britishEnglish` is a transcription post-processing flag (slice 04 territory), not a UI locale. Not wired through svelte-i18n.
+- Default locale is detected from `navigator.language`. In Tauri, this is the OS locale.
+
+## See also
+
+- [Pages: settings](pages/settings.md). The locale picker UI.
+- [Stores](stores.md). The `currentLocale` derived store.