merge(feat/person-birth-death-years): resolve conflicts with main, bump migration to V6

Resolves merge conflicts with main (feat/person-notes merged first).
Combines both features: birth/death years and notes field on person detail.
Renames migration V5__add_birth_death_years to V6 to avoid Flyway conflict.

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

frontend/src/routes/persons/[id]/+page.server.ts

@@ -28,6 +28,7 @@ export const actions = {
         const firstName = formData.get('firstName')?.toString().trim();
         const lastName = formData.get('lastName')?.toString().trim();
         const alias = formData.get('alias')?.toString().trim() || undefined;
+        const notes = formData.get('notes')?.toString().trim() || undefined;
         const birthYear = formData.get('birthYear')?.toString().trim() || undefined;
         const deathYear = formData.get('deathYear')?.toString().trim() || undefined;
 
@@ -41,6 +42,7 @@ export const actions = {
             body: {
                 firstName, lastName,
                 ...(alias ? { alias } : {}),
+                ...(notes ? { notes } : {}),
                 ...(birthYear ? { birthYear } : {}),
                 ...(deathYear ? { deathYear } : {})
             }