fix(cli): escape newlines in cypher markdown cells

A multi-line cell value (e.g. a symbol's `content`) was rendered with raw
newlines via String(v), so one logical row spanned multiple physical lines.
That corrupts the markdown table and breaks `cypher --limit`'s line-based
slice (it kept the wrong number of rows, often zero, while row_count
over-claimed). Collapse newlines in formatCypherAsMarkdown so one physical
line == one row; the existing CLI slice is now correct and the pre-existing
un---limited corruption is fixed too. (#2310 review)

gitnexus/src/mcp/local/local-backend.ts

@@ -2319,7 +2319,11 @@ export class LocalBackend {
             const v = row[k];
             if (v === null || v === undefined) return '';
             if (typeof v === 'object') return JSON.stringify(v);
-            return String(v);
+            // Collapse newlines so a multi-line cell value (e.g. a symbol's
+            // `content`) stays on one physical line. Otherwise the rendered row
+            // spans multiple lines, which corrupts the table and breaks the
+            // CLI's `--limit` line-based slicing (#2310 review).
+            return String(v).replace(/\r?\n/g, ' ');
           })
           .join(' | ') +
         ' |',

gitnexus/test/unit/calltool-dispatch.test.ts

@@ -3436,6 +3436,24 @@ describe('cypher result formatting', () => {
     expect(result.row_count).toBe(2);
   });
 
+  it('keeps one markdown line per row when a cell value contains newlines (#2310)', async () => {
+    // A multi-line `content` value must not split its row across physical lines —
+    // otherwise the rendered table is corrupt and the CLI `--limit` line-slice
+    // keeps the wrong number of rows.
+    (executeParameterized as any).mockResolvedValue([
+      { name: 'a', content: 'export function a() {\n  return 1;\n}' },
+      { name: 'b', content: 'line1\nline2' },
+    ]);
+    const result = await backend.callTool('cypher', {
+      query: 'MATCH (n:Function) RETURN n.name AS name, n.content AS content',
+    });
+    const lines = result.markdown.split('\n');
+    // header + separator + exactly one line per data row, no embedded newlines.
+    expect(lines).toHaveLength(2 + result.row_count);
+    expect(result.row_count).toBe(2);
+    expect(result.markdown).not.toMatch(/\n[^|]/);
+  });
+
   it('returns empty array as-is', async () => {
     (executeParameterized as any).mockResolvedValue([]);
     const result = await backend.callTool('cypher', {