fix(installer): Codex TOML block finder preserves trailing array-of-tables siblings (#1351) (#1370)

The Codex installer's `findNextTableHeader` skipped `[[array-of-tables]]` headers instead of treating them as a block boundary, so any `[[...]]` block after `[mcp_servers.codegraph]` in ~/.codex/config.toml was silently deleted on install/upgrade/uninstall. Now treats both `[...]` and `[[...]]` as boundaries, with a small line lexer so header-shaped text inside multiline strings/arrays isn't mistaken for a boundary. Adds round-trip regression coverage (install → reinstall → uninstall) + CHANGELOG entry.

Fixes #1351. Supersedes #624.

Thanks @KtzeAbyss.

__tests__/installer-targets.test.ts

@@ -876,6 +876,48 @@ describe('Installer targets — partial-state idempotency', () => {
     expect(after).not.toContain('enabled = true');
   });
 
+  it('codex: install, re-install, and uninstall preserve trailing array-of-tables siblings', () => {
+    const codex = getTarget('codex')!;
+    const tomlPath = path.join(tmpHome, '.codex', 'config.toml');
+    fs.mkdirSync(path.dirname(tomlPath), { recursive: true });
+    const historyTables = [
+      '[[history]]',
+      'id = 1',
+      'note = "keep first"',
+      '',
+      '[[history]]',
+      'id = 2',
+      'note = "keep second"',
+      '',
+    ].join('\n');
+    fs.writeFileSync(tomlPath, [
+      '[mcp_servers.codegraph]',
+      'command = "old-codegraph"',
+      'args = ["old"]',
+      'description = """',
+      'header-shaped text inside a multiline string:',
+      '[[not-a-table]]',
+      'still part of the string',
+      '"""',
+      '',
+      historyTables,
+    ].join('\n'));
+
+    const first = codex.install('global', { autoAllow: false });
+    expect(first.files.find((f) => f.path === tomlPath)?.action).toBe('updated');
+    const afterInstall = fs.readFileSync(tomlPath, 'utf-8');
+    expect(afterInstall).toContain('command = "codegraph"');
+    expect(afterInstall).not.toContain('[[not-a-table]]');
+    expect(afterInstall.endsWith(historyTables)).toBe(true);
+
+    const second = codex.install('global', { autoAllow: false });
+    expect(second.files.find((f) => f.path === tomlPath)?.action).toBe('unchanged');
+    expect(fs.readFileSync(tomlPath, 'utf-8')).toBe(afterInstall);
+
+    codex.uninstall('global');
+    expect(fs.readFileSync(tomlPath, 'utf-8')).toBe(historyTables);
+  });
+
   it('claude: local install writes ./.mcp.json (project scope), not ./.claude.json', () => {
     const claude = getTarget('claude')!;
     const result = claude.install('local', { autoAllow: false });
@@ -1292,6 +1334,113 @@ describe('Installer targets — TOML serializer (Codex backbone)', () => {
     expect(content.match(/\[\[foo\]\]/g)?.length).toBe(2);
     expect(content).toContain('[mcp_servers.codegraph]');
   });
+
+  it('upsert replaces the managed table without consuming trailing array-of-tables siblings', () => {
+    const historyTables = [
+      '[[history]]',
+      'id = 1',
+      'note = "keep first"',
+      '',
+      '[[history]]',
+      'id = 2',
+      'note = "keep second"',
+      '',
+    ].join('\n');
+    const existing = [
+      '[mcp_servers.codegraph]',
+      'command = "old-codegraph"',
+      'args = ["old"]',
+      '',
+      historyTables,
+    ].join('\n');
+    const block = buildTomlTable('mcp_servers.codegraph', {
+      command: 'codegraph',
+      args: ['serve', '--mcp'],
+    });
+
+    const { content, action } = upsertTomlTable(existing, 'mcp_servers.codegraph', block);
+
+    expect(action).toBe('replaced');
+    expect(content).toBe(`${block}\n\n${historyTables}`);
+  });
+
+  it('remove preserves trailing array-of-tables siblings byte-for-byte', () => {
+    const historyTables = [
+      '[[history]]',
+      'id = 1',
+      'note = "keep first"',
+      '',
+      '[[history]]',
+      'id = 2',
+      'note = "keep second"',
+      '',
+    ].join('\n');
+    const existing = [
+      '[mcp_servers.codegraph]',
+      'command = "codegraph"',
+      'args = ["serve", "--mcp"]',
+      '',
+      historyTables,
+    ].join('\n');
+
+    const { content, action } = removeTomlTable(existing, 'mcp_servers.codegraph');
+
+    expect(action).toBe('removed');
+    expect(content).toBe(historyTables);
+  });
+
+  it.each([
+    ['table', '[ mcp_servers.other ]'],
+    ['array-of-tables', '[[ history ]]'],
+  ])('preserves a trailing %s header with inner whitespace', (_kind, siblingHeader) => {
+    const siblingTable = `${siblingHeader}\nvalue = "keep"\n`;
+    const existing = [
+      '[mcp_servers.codegraph]',
+      'command = "old-codegraph"',
+      'args = ["old"]',
+      '',
+      siblingTable,
+    ].join('\n');
+    const block = buildTomlTable('mcp_servers.codegraph', {
+      command: 'codegraph',
+      args: ['serve', '--mcp'],
+    });
+
+    const upserted = upsertTomlTable(existing, 'mcp_servers.codegraph', block);
+    const removed = removeTomlTable(existing, 'mcp_servers.codegraph');
+
+    expect(upserted.content).toBe(`${block}\n\n${siblingTable}`);
+    expect(removed.content).toBe(siblingTable);
+  });
+
+  it.each([
+    ['basic', '"""'],
+    ['literal', "'''"],
+  ])('ignores header-shaped text inside a multiline %s string', (_kind, delimiter) => {
+    const historyTable = '[[history]]\nid = 1\n';
+    const existing = [
+      '[mcp_servers.codegraph]',
+      'command = "old-codegraph"',
+      'args = [',
+      `  ${delimiter}first line`,
+      '[[not-a-table]]',
+      `last line${delimiter},`,
+      '  "serve",',
+      ']',
+      '',
+      historyTable,
+    ].join('\n');
+    const block = buildTomlTable('mcp_servers.codegraph', {
+      command: 'codegraph',
+      args: ['serve', '--mcp'],
+    });
+
+    const upserted = upsertTomlTable(existing, 'mcp_servers.codegraph', block);
+    const removed = removeTomlTable(existing, 'mcp_servers.codegraph');
+
+    expect(upserted.content).toBe(`${block}\n\n${historyTable}`);
+    expect(removed.content).toBe(historyTable);
+  });
 });
 
 describe('Installer — uninstallTargets sweep (codegraph uninstall)', () => {