v3: keep pasted description images out of the dump kind and the card teasers

The dump modal's window-level paste listener looked at the clipboard files
before it looked at the event target, so an image pasted into the "Why?"
field was claimed twice: the editor uploaded it as an inline attachment,
and the modal switched itself to file mode with that same image as the
dump. Writing a URL dump with an illustrated description was impossible.
The target guard that already existed for text pastes now runs first and
covers files too — fields own their paste, and the URL input keeps its own
handler for the image-to-file-dump shortcut. Pasting onto the modal body,
where nothing else is listening, still starts a file dump.

Card teasers are line-clamped boxes, which an embedded image blows apart.
Inline markdown — the mode the dump and journal cards already ask for —
now drops img nodes, so a description image shows up on the detail page
and nowhere else.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01TiAPtJZeCYYk8rKehtLUQU

src/components/DumpCreateModal.tsx

@@ -186,6 +186,12 @@ export function DumpCreateModal(
   // Paste handler
   useEffect(() => {
     const handler = (e: ClipboardEvent) => {
+      // Fields own their paste: the comment editor uploads pasted images as
+      // inline attachments, and the URL input has its own file handler below.
+      // Without this guard, pasting an image into the description would flip
+      // the whole modal over to a file dump.
+      const tag = (e.target as HTMLElement).tagName;
+      if (tag === "INPUT" || tag === "TEXTAREA") return;
       const pastedFile = e.clipboardData?.files[0];
       if (pastedFile) {
         setMode("file");
@@ -194,8 +200,6 @@ export function DumpCreateModal(
         clearErrors("root");
         return;
       }
-      const tag = (e.target as HTMLElement).tagName;
-      if (tag === "INPUT" || tag === "TEXTAREA") return;
       const text = e.clipboardData?.getData("text") ?? "";
       try {
         const u = new URL(normalizeUrl(text));