feat(postgres): implement notes CRUD and export import

Co-Authored-By: gpt-5.6-luna <noreply@openai.com>

src/db/postgres/cast.ts

@@ -1,6 +1,7 @@
 import type { Abode } from "../types/Abode.js";
 import type { ApikeyPermissions, ClientApikey } from "../types/Apikey.js";
 import type { Resident, ResidentFlags } from "../types/Resident.js";
+import type { Note, NoteProperties, PartialNote, PartialNoteProperties } from "../types/Note.js";
 import type { ClientUser, PartialUser, UserFlags } from "../types/User.js";
 
 export function pgToDate(d: Date | string): string {
@@ -135,3 +136,66 @@ export function pgToClientApikey(apikey: {
     expires_at: apikey.expires_at ? pgToDate(apikey.expires_at) : null,
   };
 }
+
+const validNoteTypes = new Set(["note"]);
+
+function pgToNoteProperties(properties: unknown): NoteProperties {
+  if (typeof properties !== "object" || !properties || Array.isArray(properties))
+    return {};
+  const value = properties as Record<string, unknown>;
+  return validNoteTypes.has(value.type as string)
+    ? { type: value.type as "note" }
+    : {};
+}
+
+function pgToPartialNoteProperties(
+  properties: unknown,
+): PartialNoteProperties {
+  return { type: pgToNoteProperties(properties).type ?? "note" };
+}
+
+export function pgToNote(note: {
+  nid: string;
+  aid: string;
+  name: string;
+  content: string;
+  properties: unknown;
+  created_at: Date | string;
+  created_by: string | null;
+  updated_at: Date | string;
+  updated_by: string | null;
+}): Note {
+  return {
+    nid: note.nid,
+    aid: note.aid,
+    name: note.name,
+    content: note.content,
+    properties: pgToNoteProperties(note.properties),
+    created_at: pgToDate(note.created_at),
+    created_by: note.created_by,
+    updated_at: pgToDate(note.updated_at),
+    updated_by: note.updated_by,
+  };
+}
+
+export function pgToPartialNote(note: {
+  nid: string;
+  aid: string;
+  name: string;
+  properties: unknown;
+  created_at: Date | string;
+  created_by: string | null;
+  updated_at: Date | string;
+  updated_by: string | null;
+}): PartialNote {
+  return {
+    nid: note.nid,
+    aid: note.aid,
+    name: note.name,
+    properties: pgToPartialNoteProperties(note.properties),
+    created_at: pgToDate(note.created_at),
+    created_by: note.created_by,
+    updated_at: pgToDate(note.updated_at),
+    updated_by: note.updated_by,
+  };
+}