attachments sync: attach offline, upload when linked, removals stick (#5168)

Desktop could not create an attachment at all, and a removed attachment or
dismissed preview came back on the next pull. Now:

- core: add_attachment keeps the bytes in the blob store and queues the row
  (schema v10: attachments.uploaded / upload_error). Push uploads it once its
  note has landed. A refusal that retrying won't fix (too large, id clash, hash
  mismatch) is recorded on the file and not re-sent every cycle; the editor
  shows it.
- core: removing a synced attachment or dismissing a preview leaves a tombstone
  in pending_deletes; push sends it as an `attachment`/`preview` delete, and a
  pull while it waits doesn't put the row back. A pull also keeps files still
  waiting to upload instead of replacing them wholesale.
- server: PUT /api/sync/attachments/<id> (raw body, sha256-checked, idempotent,
  size-capped) and child deletes in push, which apply regardless of LWW and
  answer noop for rows the caller can't see. One store_attachment helper for
  the upload route, the importer and sync. Protocol 5, feature attachment_sync;
  the client sends neither to a server without it.
- server: migration 0031 makes a link preview's insert/delete bump its note, so
  background-fetched previews and web dismissals reach linked devices.
- desktop: Attach and paste-image work offline (raw-bytes IPC command).
- SVG is served as a download by the desktop blob scheme too (as #1981 did for
  the web), and drawn as a file chip on both.
- autosync: drop the catch_unwind; release builds abort on panic, so it only
  ever worked in debug builds.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

frontend/src/components/NoteCard.vue

@@ -2,6 +2,7 @@
 import { computed, ref, watch } from "vue";
 import { useNotesStore } from "../stores/notes";
 import { NOTE_CARD_SURFACE, labelChipClasses } from "../notes/colors";
+import { rendersInline } from "../notes/attachments";
 import type { Note } from "../stores/notes";
 import Icon from "./Icon.vue";
 import LinkPreview from "./LinkPreview.vue";
@@ -43,8 +44,8 @@ const trashCountdown = computed(() => formatTrashCountdown(trashDays.value));
 const trashUrgent = computed(() => trashDays.value !== null && trashDays.value <= 3);
 
 // The card previews the first image inline; non-image files show as compact chips.
-const firstImage = computed(() => props.note.attachments.find((a) => a.mime.startsWith("image/")));
-const otherAttachments = computed(() => props.note.attachments.filter((a) => !a.mime.startsWith("image/")));
+const firstImage = computed(() => props.note.attachments.find((a) => rendersInline(a.mime)));
+const otherAttachments = computed(() => props.note.attachments.filter((a) => !rendersInline(a.mime)));
 
 // How much of a note the CARD shows. Android has always clamped to 8
 // (`MAX_PREVIEW_LINES`); the web rendered the whole body, so one long note could

frontend/src/components/NoteEditor.vue

@@ -1,6 +1,8 @@
 <script setup lang="ts">
 import { computed, nextTick, onBeforeUnmount, onMounted, ref, watch } from "vue";
 import { useNotesStore } from "../stores/notes";
+import { errorMessage } from "../api/errors";
+import { rendersInline } from "../notes/attachments";
 import Icon from "./Icon.vue";
 import LabelPicker from "./LabelPicker.vue";
 import LinkPreview from "./LinkPreview.vue";
@@ -446,11 +448,12 @@ function addChecklist(): void {
 }
 
 // ---- attachments ----
+const refusedUploads = computed(() => liveNote.value.attachments.filter((a) => a.upload_error));
 function pickFile() {
   fileInput.value?.click();
 }
 function attKind(mime: string): "image" | "audio" | "file" {
-  if (mime.startsWith("image/")) return "image";
+  if (rendersInline(mime)) return "image";
   if (mime.startsWith("audio/")) return "audio";
   return "file";
 }
@@ -467,7 +470,7 @@ async function uploadFile(file: File) {
   try {
     await notes.uploadAttachment(id, file);
   } catch (e) {
-    uploadError.value = (e as { error?: string }).error ?? "Could not upload file.";
+    uploadError.value = errorMessage(e, "Could not upload file.");
   }
 }
 
@@ -611,6 +614,16 @@ function revPreview(rev: NoteRevision): string {
           </template>
         </div>
         <p v-if="uploadError" class="text-xs text-red-600 dark:text-red-400">{{ uploadError }}</p>
+        <!-- Desktop: a file attached here that the server refused. It isn't retried,
+             so without this line it would sit on this device unsynced and unexplained. -->
+        <p
+          v-for="att in refusedUploads"
+          :key="`refused-${att.id}`"
+          class="text-xs text-amber-600 dark:text-amber-400"
+        >
+          {{ att.filename || "A file" }} won't sync: {{ att.upload_error }}. It stays on this
+          device until you remove it.
+        </p>
 
         <!-- Fetched automatically after each save; removable here and nowhere else. -->
         <div v-if="liveNote.previews.length" class="flex flex-col gap-2">