docs(legibility): add 18 per-domain README.md files (DOC-6)

Backend (9): document, person, tag, user, geschichte, notification,
ocr, audit, dashboard.
Frontend (8): document, person, tag, user, geschichte, notification,
ocr, shared.
OCR service (1): ocr-service/README.md.

Each README covers: what the domain owns, explicit non-ownership,
public surface (verified by grep against the codebase), internal
layout, and cross-domain dependencies.

Closes #400
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/src/lib/geschichte/README.md

@@ -0,0 +1,34 @@
+# geschichte (frontend)
+
+UI for family stories: the rich-text editor, story cards, and story list view.
+
+## What this domain owns
+
+Components: `GeschichteEditor.svelte`, `GeschichtenCard.svelte`.
+
+## What this domain does NOT own
+
+- Comment/discussion UI — shared via `shared/discussion/` (same component used for document comments)
+- Person display — `person/PersonChip.svelte` is used inside story content (cross-domain import)
+- Document display — document references in stories use components from `document/`
+
+## Key components
+
+| Component                 | Used in                                      | Notes                                                              |
+| ------------------------- | -------------------------------------------- | ------------------------------------------------------------------ |
+| `GeschichteEditor.svelte` | `/geschichten/new`, `/geschichten/[id]/edit` | Rich-text editor with person/document @-mentions and inline embeds |
+| `GeschichtenCard.svelte`  | `/geschichten` (list), dashboard             | Story preview card with cover image and publish status             |
+
+## Audience note
+
+The `/geschichten` route primarily serves readers (younger family members on mobile). Cards must have ≥ 44 px touch targets. Status must not rely on color alone.
+
+## Cross-domain imports
+
+- `person/PersonChip.svelte` — inline person references in story content
+- `document/DocumentThumbnail.svelte` — inline document references
+- `shared/discussion/` — comment thread below published stories
+
+## Backend counterpart
+
+`backend/src/main/java/org/raddatz/familienarchiv/geschichte/README.md`