Fiks: bevar metadata ved rebuildMessages, sett edited_at ved AI-behandling

- rebuildMessages bevarer nå PG-felter (metadata, edited_at, reply_count)
  fra eksisterende meldinger i stedet for å overskrive med undefined
- Worker setter edited_at = now() ved AI-behandling slik at
  revisjonshistorikk og AI-badge vises umiddelbart

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

web/src/lib/chat/spacetime.svelte.ts

@@ -90,7 +90,20 @@ export function createSpacetimeChat(
 			const bMs = extractMs(b.createdAt);
 			return aMs - bMs;
 		});
-		messages = rows.map(r => spacetimeRowToMessage(r));
+		// Bevar PG-spesifikke felter (metadata, edited_at, reply_count, etc.) fra eksisterende meldinger
+		const existing = new Map(messages.map(m => [m.id, m]));
+		messages = rows.map(r => {
+			const msg = spacetimeRowToMessage(r);
+			const prev = existing.get(msg.id);
+			if (prev) {
+				msg.metadata = prev.metadata;
+				msg.edited_at = prev.edited_at;
+				msg.reply_count = prev.reply_count;
+				msg.parent_body = prev.parent_body;
+				msg.parent_author_name = prev.parent_author_name;
+			}
+			return msg;
+		});
 	}
 
 	function extractMs(ts: any): number {

worker/src/handlers/ai_text_process.rs

@@ -234,7 +234,8 @@ impl AiTextProcessHandler {
         sqlx::query(
             r#"
             UPDATE messages
-            SET metadata = (COALESCE(metadata, '{}'::jsonb) - 'ai_processing') || $1::jsonb
+            SET metadata = (COALESCE(metadata, '{}'::jsonb) - 'ai_processing') || $1::jsonb,
+                edited_at = now()
             WHERE id = $2
             "#,
         )