feat(relationship): editable relationships with LocalDate+DatePrecision dates and notes (#841)

Closes #837

Makes `PersonRelationship` fully editable (type, related person, dates, notes), migrates its dates from `Integer fromYear/toYear` to `LocalDate + DatePrecision` (mirroring the #773 person pattern, ADR-039 / V76), activates the previously-dead `notes` column, and gives the Zeitstrahl's derived **Heirat** events full date precision for free.

Both Open Decisions confirmed as adopted: **no `@Version`** (last-write-wins, single-writer archive) and **`DELETE` ownership-mismatch aligned 403 → 404** (anti-enumeration, matching the new `PUT`).

## What's in it
- **V78** migrates `person_relationships.from_year/to_year` → `from_date`/`to_date` + NOT-NULL `*_date_precision` (default `UNKNOWN`); pre-check abort on corrupt years, `YYYY-01-01`/`YEAR` backfill, 5 named CHECK constraints, year columns dropped.
- **`PUT /api/persons/{id}/relationships/{relId}`** (`@RequirePermission(WRITE_ALL)`) re-runs every create invariant (self / coherence / order / reverse-PARENT_OF / duplicate) and re-flags family membership; orientation preserved per viewpoint.
- New `ErrorCode.INVALID_RELATIONSHIP_DATES` registered in all four sites (§3.6).
- `TimelineEventService` sources the derived marriage date from `SPOUSE_OF.fromDate` + precision.
- Frontend: `RelationshipDateField` (DAY/MONTH/YEAR), upsert-capable `AddRelationshipForm` (pre-fill + notes + in-flight submit lock), `RelationshipChip` Edit affordance, `updateRelationship` server action, read-view date range + notes, `formatRelationshipDateRange` helper. `api.ts` regenerated.
- Docs: ADR-044, db-orm/db-relationships diagrams, DEPLOYMENT §5 deploy note, RTM REQ-001…REQ-019.

## Requirements
All 19 EARS requirements implemented red/green and marked `Done` in `.specify/rtm.md`.

## Test plan
- **Backend** (targeted, green): `RelationshipMigrationTest` (Testcontainers pg16, 8), `RelationshipServiceTest` (22), `RelationshipControllerTest` (15), `RelationshipServiceIntegrationTest` (real DB, 10), `DerivedEventsAssemblyTest` (17), `ArchitectureTest` (14); `clean package` builds.
- **Frontend** (green): `relationshipDates.spec.ts`, `AddRelationshipForm.svelte.spec.ts`, `RelationshipChip.svelte.spec.ts`, `PersonRelationshipsCard.svelte.test.ts`, `page.server.spec.ts`, `messages.spec.ts`. `npm run check` = 798 (below the ~834 baseline); `npm run lint` clean.

## Notes for reviewers
- **Spec deviation:** the edit form was built by making `AddRelationshipForm` upsert-capable rather than a duplicate `EditRelationshipForm` (DRY); RTM rows reference `AddRelationshipForm.svelte.spec.ts`.
- `api.ts` regenerated from the live spec; only relationship-relevant hunks remain (one springdoc `PageableObject` field-reorder pruned).
- **Deploy:** V78 is one-way and not rolling-deploy-safe — stop old JAR → start new JAR (Flyway runs first); targeted `pg_restore -t person_relationships` for rollback. No maintenance window.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-authored-by: Marcel <marcel@familienarchiv>
Reviewed-on: #841

frontend/src/lib/person/relationship/AddRelationshipForm.svelte

@@ -1,8 +1,11 @@
 <script lang="ts">
+import { onMount } from 'svelte';
 import { enhance } from '$app/forms';
 import { m } from '$lib/paraglide/messages.js';
 import PersonTypeahead from '$lib/person/PersonTypeahead.svelte';
+import RelationshipDateField from '$lib/person/relationship/RelationshipDateField.svelte';
 import type { components } from '$lib/generated/api';
+import type { DatePrecision } from '$lib/shared/utils/documentDate';
 
 type RelationshipDTO = components['schemas']['RelationshipDTO'];
 type RelationType = NonNullable<RelationshipDTO['relationType']>;
@@ -10,71 +13,96 @@ type RelationType = NonNullable<RelationshipDTO['relationType']>;
 export type RelFormData = {
 	relatedPersonId: string;
 	relationType: RelationType;
-	fromYear?: number;
-	toYear?: number;
+	fromDate?: string;
+	fromDatePrecision?: DatePrecision;
+	toDate?: string;
+	toDatePrecision?: DatePrecision;
+	notes?: string;
 };
 
 interface Props {
 	personId: string;
+	// When present the form is an EDIT: pre-filled and posting to ?/updateRelationship.
+	relationship?: RelationshipDTO;
 	onSubmit?: (data: RelFormData) => Promise<void>;
+	onClose?: () => void;
 }
 
-let { personId, onSubmit }: Props = $props();
+let { personId, relationship, onSubmit, onClose }: Props = $props();
+
+const isEdit = $derived(relationship != null);
 
 let open = $state(false);
 let addType = $state<RelationType>('PARENT_OF');
 let addRelatedPersonId = $state('');
 let addRelatedPersonName = $state('');
-let addFromYear = $state('');
-let addToYear = $state('');
+let notes = $state('');
 let callbackError = $state<string | null>(null);
+let submitting = $state(false);
 
-const yearError = $derived.by(() => {
-	const from = addFromYear.trim();
-	const to = addToYear.trim();
-	if (!from || !to) return null;
-	const fromInt = parseInt(from, 10);
-	const toInt = parseInt(to, 10);
-	if (Number.isNaN(fromInt) || Number.isNaN(toInt)) return null;
-	return toInt < fromInt ? m.relation_year_error_bis_before_von() : null;
+// Seed once at mount (reading props in a closure avoids state_referenced_locally).
+// The parent re-creates this form per edited row, so the relationship never
+// changes under a live instance.
+onMount(() => {
+	if (!relationship) return;
+	open = true;
+	addType = relationship.relationType ?? 'PARENT_OF';
+	const viewpointIsSubject = relationship.personId === personId;
+	addRelatedPersonId =
+		(viewpointIsSubject ? relationship.relatedPersonId : relationship.personId) ?? '';
+	addRelatedPersonName =
+		(viewpointIsSubject ? relationship.relatedPersonDisplayName : relationship.personDisplayName) ??
+		'';
+	notes = relationship.notes ?? '';
 });
 
 const selfError = $derived(
 	addRelatedPersonId !== '' && addRelatedPersonId === personId ? m.relation_error_self() : null
 );
 
-const submitDisabled = $derived(
-	yearError !== null || selfError !== null || addRelatedPersonId === ''
-);
+const submitDisabled = $derived(selfError !== null || addRelatedPersonId === '');
 
 function reset() {
 	addType = 'PARENT_OF';
 	addRelatedPersonId = '';
 	addRelatedPersonName = '';
-	addFromYear = '';
-	addToYear = '';
+	notes = '';
 	callbackError = null;
 }
 
 function cancel() {
+	if (isEdit) {
+		onClose?.();
+		return;
+	}
 	open = false;
 	reset();
 }
 
-async function handleCallbackSubmit(event: Event) {
+async function handleCallbackSubmit(event: SubmitEvent) {
 	event.preventDefault();
 	if (submitDisabled || !onSubmit) return;
-	const data: RelFormData = { relatedPersonId: addRelatedPersonId, relationType: addType };
-	const from = parseInt(addFromYear.trim(), 10);
-	if (!Number.isNaN(from)) data.fromYear = from;
-	const to = parseInt(addToYear.trim(), 10);
-	if (!Number.isNaN(to)) data.toYear = to;
+	const fd = new FormData(event.currentTarget as HTMLFormElement);
+	const fromDate = (fd.get('fromDate') as string) || undefined;
+	const toDate = (fd.get('toDate') as string) || undefined;
+	const data: RelFormData = {
+		relatedPersonId: addRelatedPersonId,
+		relationType: addType,
+		fromDate,
+		fromDatePrecision: fromDate ? (fd.get('fromDatePrecision') as DatePrecision) : undefined,
+		toDate,
+		toDatePrecision: toDate ? (fd.get('toDatePrecision') as DatePrecision) : undefined,
+		notes: (fd.get('notes') as string)?.trim() || undefined
+	};
+	submitting = true;
 	try {
 		await onSubmit(data);
 		open = false;
 		reset();
 	} catch {
 		callbackError = m.error_internal_error();
+	} finally {
+		submitting = false;
 	}
 }
 </script>
@@ -113,39 +141,32 @@ async function handleCallbackSubmit(event: Event) {
 				compact
 			/>
 		</div>
-		<label class="block">
-			<span class="font-sans text-xs font-medium text-ink-2"
-				>{m.relation_form_field_from_year()}</span
-			>
-			<input
-				type="text"
-				name="fromYear"
-				inputmode="numeric"
-				pattern="[0-9]*"
-				bind:value={addFromYear}
-				placeholder={m.relation_form_year_placeholder()}
-				class="mt-1 block w-full rounded-sm border border-line bg-surface px-2 py-1.5 text-sm text-ink focus:border-primary focus:outline-none"
-			/>
-		</label>
-		<label class="block">
-			<span class="font-sans text-xs font-medium text-ink-2">{m.relation_form_field_to_year()}</span
-			>
-			<input
-				type="text"
-				name="toYear"
-				inputmode="numeric"
-				pattern="[0-9]*"
-				bind:value={addToYear}
-				aria-describedby={yearError ? 'add-rel-year-error' : undefined}
-				class="mt-1 block w-full rounded-sm border border-line bg-surface px-2 py-1.5 text-sm text-ink focus:border-primary focus:outline-none"
-			/>
-			{#if yearError}
-				<p id="add-rel-year-error" class="mt-1 text-xs text-red-700" role="alert">
-					{yearError}
-				</p>
-			{/if}
-		</label>
 	</div>
+	<div class="mt-3 grid gap-3 md:grid-cols-2">
+		<RelationshipDateField
+			name="fromDate"
+			legend={m.relation_label_from_date()}
+			initialIso={relationship?.fromDate ?? ''}
+			initialPrecision={relationship?.fromDatePrecision ?? null}
+		/>
+		<RelationshipDateField
+			name="toDate"
+			legend={m.relation_label_to_date()}
+			initialIso={relationship?.toDate ?? ''}
+			initialPrecision={relationship?.toDatePrecision ?? null}
+		/>
+	</div>
+	<label class="mt-3 block">
+		<span class="font-sans text-xs font-medium text-ink-2">{m.relation_label_notes()}</span>
+		<textarea
+			name="notes"
+			maxlength="2000"
+			rows="2"
+			bind:value={notes}
+			placeholder={m.relation_notes_placeholder()}
+			class="mt-1 block w-full rounded-sm border border-line bg-surface px-2 py-1.5 font-serif text-sm text-ink-3 focus:border-primary focus:outline-none"
+		></textarea>
+	</label>
 	{#if selfError}
 		<p class="mt-2 text-xs text-red-700" role="alert">{selfError}</p>
 	{/if}
@@ -162,10 +183,18 @@ async function handleCallbackSubmit(event: Event) {
 		</button>
 		<button
 			type="submit"
-			disabled={submitDisabled}
-			class="rounded-sm bg-primary px-3 py-1.5 font-sans text-xs font-medium text-primary-fg transition hover:bg-primary/80 disabled:opacity-40"
+			disabled={submitDisabled || submitting}
+			aria-busy={submitting}
+			class="inline-flex items-center gap-1.5 rounded-sm bg-primary px-3 py-1.5 font-sans text-xs font-medium text-primary-fg transition hover:bg-primary/80 disabled:opacity-40"
 		>
-			{m.relation_btn_add()}
+			{#if submitting}
+				<span
+					class="h-3 w-3 animate-spin rounded-full border-2 border-primary-fg/40 border-t-primary-fg"
+					data-testid="submit-spinner"
+					aria-hidden="true"
+				></span>
+			{/if}
+			{isEdit ? m.relation_btn_save() : m.relation_btn_add()}
 		</button>
 	</div>
 {/snippet}
@@ -185,18 +214,27 @@ async function handleCallbackSubmit(event: Event) {
 {:else}
 	<form
 		method="POST"
-		action="?/addRelationship"
+		action={isEdit ? '?/updateRelationship' : '?/addRelationship'}
 		use:enhance={() => {
+			submitting = true;
 			return async ({ result, update }) => {
 				await update();
+				submitting = false;
 				if (result.type === 'success') {
-					open = false;
-					reset();
+					if (isEdit) {
+						onClose?.();
+					} else {
+						open = false;
+						reset();
+					}
 				}
 			};
 		}}
 		class="mt-3 rounded-sm border border-line bg-muted/40 p-3"
 	>
+		{#if relationship}
+			<input type="hidden" name="relId" value={relationship.id} />
+		{/if}
 		{@render formFields()}
 	</form>
 {/if}