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/pages/first-run.md

@@ -0,0 +1,59 @@
+---
+name: First run page
+type: architecture-map-page
+slice: 01-frontend
+last_verified: 2026/05/09
+---
+
+# First run page
+
+> **Where you are:** [Architecture map](../../README.md) → [Frontend](../README.md) → [Pages overview](../pages-overview.md) → First run
+
+**Plain English summary.** What the user sees the first time they launch Magnotia, before any model is on disk. Probes hardware, recommends a Whisper model size, and downloads the chosen model (Whisper or Parakeet). On success, transitions to the dictation page.
+
+## At a glance
+
+- **Path:** `src/lib/pages/FirstRunPage.svelte`
+- **LOC:** 337
+- **Imports:**
+  - Tauri: `invoke`, `listen`.
+  - Stores: `page`, `settings`, `saveSettings` from `page.svelte.ts`. `toasts`.
+  - Components: `UnicodeSpinner`.
+  - External: `lucide-svelte` (`Download`, `CheckCircle`, `Sunrise`, `Moon`, `Play`).
+- **Includes:** also `ShutdownRitualPage` is imported here (suggesting the "evening ritual" preview lives in this same flow). Verify on read; treat as a coupled flow.
+
+## What's in here
+
+### Probe
+
+- `onMount` calls `probe_system` and `rank_models` (`FirstRunPage.svelte:31-32`) to compute recommended models given the user's RAM, GPU, OS.
+- Sets `probing = false` and renders the recommendation UI.
+
+### Download
+
+- `downloadAndGo(modelId)` (`FirstRunPage.svelte:55-95`):
+  - Subscribes to `model-download-progress` and `parakeet-download-progress` events.
+  - Calls `download_model` then `load_model` (Whisper) or `download_parakeet_model` then `load_parakeet_model`.
+  - On success, sets `ready = true` and routes to dictation (`page.current = "dictation"`).
+  - Computes `estimatedMinutes` from elapsed and progress percent (`derived.by`).
+
+### Triggering
+
+- The shell auto sets `page.current = "first-run"` if `list_models` and `list_parakeet_models` are both empty (`+layout.svelte:346-353`).
+- Skip path: clicking "Get started" without a model lets the user opt out (still routes to dictation).
+
+## Tauri command surface
+
+`probe_system`, `rank_models`, `download_model`, `load_model`, `download_parakeet_model`, `load_parakeet_model`. Events: `model-download-progress`, `parakeet-download-progress`.
+
+## Watch outs
+
+- The download is a single shot. There is no resume on cancel; if the user closes the app mid download, they restart from zero. Slice 02/05 may improve this later.
+- `estimatedMinutes` is a linear extrapolation. Network speed is not constant; expect the value to wiggle.
+- The page imports `ShutdownRitualPage` but the value of doing so should be confirmed (potential dead import).
+
+## See also
+
+- [Pages overview](../pages-overview.md). When this page is forced.
+- [Frontend ↔ Tauri bridge](../frontend-tauri-bridge.md). Probe and download commands.
+- [Windows and routes](../windows-and-routes.md). Shell triggers.