feat(mvp): phase 8 - integration, testing & deployment

Fix all build/type/lint errors (zod 3.25 compat wrapper, Svelte 5 fixes),
write 115 unit tests across 10 test files, expand seed script with demo
data, update Docker config with migration on startup.

src/lib/components/admin/PermissionEditor.svelte

@@ -117,7 +117,7 @@
 					class="w-full rounded border border-input bg-background px-2 py-1.5 text-sm text-foreground"
 				>
 					<option value="" disabled>Select...</option>
-					{#each entityOptions as option}
+					{#each entityOptions as option (option.id)}
 						<option value={option.id}>{option.name}</option>
 					{/each}
 				</select>
@@ -142,7 +142,7 @@
 					class="w-full rounded border border-input bg-background px-2 py-1.5 text-sm text-foreground"
 				>
 					<option value="" disabled>Select...</option>
-					{#each targetOptions as option}
+					{#each targetOptions as option (option.id)}
 						<option value={option.id}>{option.name}</option>
 					{/each}
 				</select>