Rewrite app: entries → projects with S3 file storage

Replace flat text entries with project-based structure.
Each project has name, local/corp fields, content textarea,
and file upload (up to 100MB) stored in MinIO S3.
New API: CRUD projects + file download + content copy.
Frontend: two views (project list + project page).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/src/App.css

@@ -9,26 +9,25 @@ h1 {
   margin-bottom: 1.5rem;
 }
 
+h2 {
+  margin-bottom: 1rem;
+}
+
 .create-section {
   display: flex;
-  flex-direction: column;
   gap: 0.5rem;
   margin-bottom: 2rem;
 }
 
-.create-section textarea {
-  width: 100%;
-  padding: 0.75rem;
+.create-section input {
+  flex: 1;
+  padding: 0.5rem 0.75rem;
   font-size: 1rem;
   border: 1px solid #ccc;
   border-radius: 4px;
-  resize: vertical;
-  font-family: inherit;
-  box-sizing: border-box;
 }
 
 .create-section button {
-  align-self: flex-end;
   padding: 0.5rem 1.5rem;
   font-size: 1rem;
   cursor: pointer;
@@ -42,51 +41,121 @@ h1 {
   background: #555;
 }
 
-.entries-list {
+.projects-list {
   display: flex;
   flex-direction: column;
-  gap: 1rem;
+  gap: 0.5rem;
 }
 
-.entry {
-  border: 1px solid #ddd;
-  border-radius: 4px;
-  padding: 1rem;
-}
-
-.entry-content {
-  margin: 0 0 0.75rem 0;
-  white-space: pre-wrap;
-  word-wrap: break-word;
-  font-family: inherit;
-  font-size: 1rem;
-}
-
-.entry-meta {
+.project-item {
   display: flex;
   justify-content: space-between;
   align-items: center;
+  padding: 0.75rem 1rem;
+  border: 1px solid #ddd;
+  border-radius: 4px;
+  cursor: pointer;
 }
 
-.entry-date {
+.project-item:hover {
+  background: #f5f5f5;
+}
+
+.project-name {
+  font-weight: 500;
+}
+
+.project-date {
   color: #888;
   font-size: 0.85rem;
 }
 
-.entry-actions {
-  display: flex;
-  gap: 0.5rem;
-}
-
-.entry-actions button {
-  padding: 0.25rem 0.75rem;
-  font-size: 0.85rem;
+.back-btn {
+  padding: 0.4rem 1rem;
+  font-size: 0.9rem;
   cursor: pointer;
   border: 1px solid #ccc;
   border-radius: 4px;
   background: white;
+  margin-bottom: 1rem;
 }
 
-.entry-actions button:hover {
+.back-btn:hover {
   background: #f0f0f0;
 }
+
+.field-group {
+  margin-bottom: 1rem;
+}
+
+.field-group label {
+  display: block;
+  margin-bottom: 0.25rem;
+  font-weight: 500;
+  font-size: 0.9rem;
+}
+
+.field-group input[type="text"] {
+  width: 100%;
+  padding: 0.5rem 0.75rem;
+  font-size: 1rem;
+  border: 1px solid #ccc;
+  border-radius: 4px;
+  box-sizing: border-box;
+}
+
+.field-group textarea {
+  width: 100%;
+  padding: 0.75rem;
+  font-size: 1rem;
+  border: 1px solid #ccc;
+  border-radius: 4px;
+  resize: vertical;
+  font-family: inherit;
+  box-sizing: border-box;
+}
+
+.field-group input[type="file"] {
+  font-size: 0.9rem;
+}
+
+.file-info {
+  display: block;
+  margin-top: 0.25rem;
+  color: #666;
+  font-size: 0.85rem;
+}
+
+.actions {
+  display: flex;
+  gap: 0.5rem;
+  margin-top: 1.5rem;
+  flex-wrap: wrap;
+}
+
+.actions button {
+  padding: 0.5rem 1.25rem;
+  font-size: 1rem;
+  cursor: pointer;
+  border: 1px solid #ccc;
+  border-radius: 4px;
+  background: #333;
+  color: white;
+}
+
+.actions button:hover {
+  background: #555;
+}
+
+.actions button:disabled {
+  opacity: 0.6;
+  cursor: not-allowed;
+}
+
+.actions button.danger {
+  background: #c0392b;
+}
+
+.actions button.danger:hover {
+  background: #e74c3c;
+}