收口 MNote P0 P1 P2 审查尾项

- 归档 OnlyOffice live bridge、Page AI、mindmap、design governance 与相关 bug 条目
- 补齐 MinerU OCR 后端 runtime 合同与 smoke/test 基线
- 收口 ChatOnly/Doubao、ObjectIdentity、Page Aggregate compat 与 runtime owner 文档口径

验证：
- cargo test --manifest-path rust/Cargo.toml -p mnote-web local_ocr -- --test-threads=1
- cargo test --manifest-path rust/Cargo.toml -p mnote-web onlyoffice_bridge -- --test-threads=1
- git diff --check
- git diff --cached --check
- codegraph index . --force && codegraph status .
- codegraph sync . && codegraph status .

rust/spikes/leptos-tiptap-spike/src/editor_runtime/style.rs

@@ -208,12 +208,32 @@ pub(crate) const SPIKE_STYLE: &str = r#"
 }
 
 .mnote-mindmap-placeholder {
+  position: relative;
   width: min(1280px, calc(100vw - 340px));
+  min-width: min(900px, calc(100vw - 80px));
+  max-width: var(--mnote-mindmap-block-max-width, none);
   margin: 10px 0;
   margin-left: 50%;
   transform: translateX(-50%);
 }
 
+.mnote-mindmap-resize-preview {
+  position: absolute;
+  top: 0;
+  left: 50%;
+  z-index: 8;
+  box-sizing: border-box;
+  pointer-events: none;
+  transform: translateX(-50%);
+  border: 1px dashed rgba(37, 99, 235, 0.78);
+  border-radius: 8px;
+  background: rgba(37, 99, 235, 0.05);
+}
+
+.mnote-mindmap-resize-preview[hidden] {
+  display: none;
+}
+
 .mnote-mindmap-editor-root {
   position: relative;
   overflow: hidden;
@@ -231,6 +251,57 @@ pub(crate) const SPIKE_STYLE: &str = r#"
   flex-direction: column;
 }
 
+.mnote-mindmap-placeholder[data-mnote-mindmap-resized="true"] .mnote-leptos-mindmap-shell {
+  min-height: 0;
+}
+
+.mnote-mindmap-resize-handle {
+  position: absolute;
+  z-index: 9;
+  width: 12px;
+  height: 12px;
+  padding: 0;
+  border: 1px solid rgba(37, 99, 235, 0.72);
+  border-radius: 50%;
+  background: #ffffff;
+  box-shadow: 0 1px 4px rgba(15, 23, 42, 0.18);
+  opacity: 0;
+  transition: opacity 120ms ease, transform 120ms ease;
+}
+
+.mnote-mindmap-editor-root:hover .mnote-mindmap-resize-handle,
+.mnote-mindmap-placeholder[data-mnote-mindmap-resizing="true"] .mnote-mindmap-resize-handle {
+  opacity: 1;
+}
+
+.mnote-mindmap-resize-handle:hover {
+  transform: scale(1.12);
+}
+
+.mnote-mindmap-resize-handle-nw {
+  top: 6px;
+  left: 6px;
+  cursor: nwse-resize;
+}
+
+.mnote-mindmap-resize-handle-ne {
+  top: 6px;
+  right: 6px;
+  cursor: nesw-resize;
+}
+
+.mnote-mindmap-resize-handle-sw {
+  bottom: 6px;
+  left: 6px;
+  cursor: nesw-resize;
+}
+
+.mnote-mindmap-resize-handle-se {
+  right: 6px;
+  bottom: 6px;
+  cursor: nwse-resize;
+}
+
 .mnote-mindmap-command-toolbar,
 .mnote-mindmap-bottom-bar {
   display: flex;