docs(timeline): register timeline domain in package tables and diagrams

Add timeline/ to the root and backend package tables, TimelineEvent to the
domain-model entity tables, TimelineEvent/EventType/Zeitstrahl to the
glossary, a new l3-backend-timeline C4 component diagram, and the
timeline_events table + two join tables (with their CHECKs and cascade FKs)
to the db-orm and db-relationships ER diagrams. Bumps the db-orm snapshot to
V77.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

CLAUDE.md

@@ -95,6 +95,7 @@ backend/src/main/java/org/raddatz/familienarchiv/
 │   └── relationship/    PersonRelationship sub-domain
 ├── security/            SecurityConfig, Permission, @RequirePermission, PermissionAspect
 ├── tag/                 Tag domain
+├── timeline/            Timeline (Zeitstrahl) domain — TimelineEvent, EventType, TimelineEventRepository
 └── user/                User domain — AppUser, UserGroup, UserService
 ```
 
@@ -115,6 +116,7 @@ backend/src/main/java/org/raddatz/familienarchiv/
 | `UserGroup`   | `user_groups`   | Has a `Set<String> permissions`                                                         |
 | `Geschichte`  | `geschichten`   | `GeschichteType` (`STORY`/`JOURNEY`); ManyToMany `persons` (Person); OneToMany `items` (JourneyItem) |
 | `JourneyItem` | `journey_items` | ManyToOne `geschichte` (Geschichte, ON DELETE CASCADE); ManyToOne `document` (Document, ON DELETE SET NULL); `position`, optional `note` |
+| `TimelineEvent` | `timeline_events` | `EventType` (`PERSONAL`/`HISTORICAL`); ManyToMany `persons` (Person) + `documents` (Document), both join FKs ON DELETE CASCADE; `DatePrecision` date block; `@Version` + NOT NULL `createdBy`/`updatedBy` audit trail |
 
 **`DocumentStatus` lifecycle:** `PLACEHOLDER → UPLOADED → TRANSCRIBED → REVIEWED → ARCHIVED`