Add MarkdownEditor component, asset image upload, and rich description editing

Introduce MarkdownEditor built on @mdxeditor/editor with headings,
lists, links, quotes, image upload with drag-and-drop, and themed CSS
integration. Add asset image upload API (routes, service, storage) and
wire image upload into InlineEditor multiline mode, NewIssueDialog,
NewProjectDialog, GoalDetail, IssueDetail, and ProjectDetail
description fields. Tighten prompt template editor styling.

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

ui/src/components/NewProjectDialog.tsx

@@ -1,9 +1,10 @@
-import { useState } from "react";
+import { useRef, useState } from "react";
 import { useQuery, useMutation, useQueryClient } from "@tanstack/react-query";
 import { useDialog } from "../context/DialogContext";
 import { useCompany } from "../context/CompanyContext";
 import { projectsApi } from "../api/projects";
 import { goalsApi } from "../api/goals";
+import { assetsApi } from "../api/assets";
 import { queryKeys } from "../lib/queryKeys";
 import {
   Dialog,
@@ -22,6 +23,7 @@ import {
   Calendar,
 } from "lucide-react";
 import { cn } from "../lib/utils";
+import { MarkdownEditor, type MarkdownEditorRef } from "./MarkdownEditor";
 import { StatusBadge } from "./StatusBadge";
 import type { Goal } from "@paperclip/shared";
 
@@ -46,6 +48,7 @@ export function NewProjectDialog() {
 
   const [statusOpen, setStatusOpen] = useState(false);
   const [goalOpen, setGoalOpen] = useState(false);
+  const descriptionEditorRef = useRef<MarkdownEditorRef>(null);
 
   const { data: goals } = useQuery({
     queryKey: queryKeys.goals.list(selectedCompanyId!),
@@ -63,6 +66,13 @@ export function NewProjectDialog() {
     },
   });
 
+  const uploadDescriptionImage = useMutation({
+    mutationFn: async (file: File) => {
+      if (!selectedCompanyId) throw new Error("No company selected");
+      return assetsApi.uploadImage(selectedCompanyId, file, "projects/drafts");
+    },
+  });
+
   function reset() {
     setName("");
     setDescription("");
@@ -145,20 +155,29 @@ export function NewProjectDialog() {
             placeholder="Project name"
             value={name}
             onChange={(e) => setName(e.target.value)}
+            onKeyDown={(e) => {
+              if (e.key === "Tab" && !e.shiftKey) {
+                e.preventDefault();
+                descriptionEditorRef.current?.focus();
+              }
+            }}
             autoFocus
           />
         </div>
 
         {/* Description */}
         <div className="px-4 pb-2">
-          <textarea
-            className={cn(
-              "w-full bg-transparent outline-none text-sm text-muted-foreground placeholder:text-muted-foreground/40 resize-none",
-              expanded ? "min-h-[160px]" : "min-h-[48px]"
-            )}
-            placeholder="Add description..."
+          <MarkdownEditor
+            ref={descriptionEditorRef}
             value={description}
-            onChange={(e) => setDescription(e.target.value)}
+            onChange={setDescription}
+            placeholder="Add description..."
+            bordered={false}
+            contentClassName={cn("text-sm text-muted-foreground", expanded ? "min-h-[220px]" : "min-h-[120px]")}
+            imageUploadHandler={async (file) => {
+              const asset = await uploadDescriptionImage.mutateAsync(file);
+              return asset.contentPath;
+            }}
           />
         </div>