fix(history): preserve empty Claude page cursors

Keep empty CLI and stdin cursors as the latest-page sentinel so session reloads do not return an empty first page. Cover positional and JSON bridge requests while preserving explicit turn zero pagination.

ai-bridge/channel-manager.protocol.test.mjs

@@ -1,8 +1,11 @@
 import test from 'node:test';
 import assert from 'node:assert/strict';
 import { spawnSync } from 'node:child_process';
+import fs from 'node:fs';
+import os from 'node:os';
 import { fileURLToPath } from 'node:url';
 import { dirname, join } from 'node:path';
+import { getClaudeProjectKey } from './utils/path-utils.js';
 
 const bridgeDir = dirname(fileURLToPath(import.meta.url));
 const channelManager = join(bridgeDir, 'channel-manager.js');
@@ -21,3 +24,83 @@ test('system command keeps stdout reserved for its JSON response', () => {
   assert.equal(typeof response.success, 'boolean');
   assert.equal(typeof response.available, 'boolean');
 });
+
+test('Claude session-page command treats empty cursors as the latest page', () => {
+  const homeDir = fs.mkdtempSync(join(os.tmpdir(), 'cc-gui-page-cursor-'));
+  const cwd = join(homeDir, 'project');
+  const sessionId = 'page-cursor-regression';
+  const sessionDir = join(homeDir, '.claude', 'projects', getClaudeProjectKey(cwd));
+  const sessionFile = join(sessionDir, `${sessionId}.jsonl`);
+
+  try {
+    fs.mkdirSync(cwd, { recursive: true });
+    fs.mkdirSync(sessionDir, { recursive: true });
+    fs.writeFileSync(sessionFile, [
+      JSON.stringify({ type: 'user', uuid: 'u1', message: { role: 'user', content: 'first' } }),
+      JSON.stringify({ type: 'assistant', message: { role: 'assistant', content: 'first reply' } }),
+      JSON.stringify({ type: 'user', uuid: 'u2', message: { role: 'user', content: 'second' } }),
+      JSON.stringify({ type: 'assistant', message: { role: 'assistant', content: 'second reply' } }),
+    ].join('\n') + '\n');
+
+    const result = spawnSync(
+      process.execPath,
+      [channelManager, 'claude', 'getSessionPage', sessionId, cwd, '', '30'],
+      {
+        cwd: bridgeDir,
+        env: { ...process.env, HOME: homeDir, USERPROFILE: homeDir },
+        encoding: 'utf8',
+        timeout: 10_000,
+      },
+    );
+
+    assert.equal(result.status, 0, result.stderr);
+    const response = JSON.parse(result.stdout.trim());
+    assert.equal(response.success, true);
+    assert.equal(response.fromTurn, 0);
+    assert.equal(response.toTurn, 2);
+    assert.equal(response.totalTurns, 2);
+    assert.equal(response.messages.length, 4);
+
+    const stdinCursors = ['', '   ', false, []];
+    for (const beforeTurn of stdinCursors) {
+      const stdinResult = spawnSync(
+        process.execPath,
+        [channelManager, 'claude', 'getSessionPage'],
+        {
+          cwd: bridgeDir,
+          env: { ...process.env, HOME: homeDir, USERPROFILE: homeDir, CLAUDE_USE_STDIN: 'true' },
+          input: JSON.stringify({ sessionId, cwd, beforeTurn, limit: 30 }),
+          encoding: 'utf8',
+          timeout: 10_000,
+        },
+      );
+
+      assert.equal(stdinResult.status, 0, stdinResult.stderr);
+      const stdinResponse = JSON.parse(stdinResult.stdout.trim());
+      assert.equal(stdinResponse.success, true);
+      assert.equal(stdinResponse.fromTurn, 0);
+      assert.equal(stdinResponse.toTurn, 2);
+      assert.equal(stdinResponse.totalTurns, 2);
+      assert.equal(stdinResponse.messages.length, 4);
+    }
+
+    const firstPageResult = spawnSync(
+      process.execPath,
+      [channelManager, 'claude', 'getSessionPage', sessionId, cwd, '0', '30'],
+      {
+        cwd: bridgeDir,
+        env: { ...process.env, HOME: homeDir, USERPROFILE: homeDir },
+        encoding: 'utf8',
+        timeout: 10_000,
+      },
+    );
+
+    assert.equal(firstPageResult.status, 0, firstPageResult.stderr);
+    const firstPage = JSON.parse(firstPageResult.stdout.trim());
+    assert.equal(firstPage.success, true);
+    assert.equal(firstPage.toTurn, 0);
+    assert.equal(firstPage.messages.length, 0);
+  } finally {
+    fs.rmSync(homeDir, { recursive: true, force: true });
+  }
+});

ai-bridge/channels/claude-channel.js

@@ -77,7 +77,11 @@ export async function handleClaudeCommand(command, args, stdinData) {
       const sessionId = stdinData?.sessionId || args[0];
       const cwd = stdinData?.cwd || args[1] || null;
       const beforeTurnRaw = stdinData?.beforeTurn ?? (args[2] !== '' && args[2] !== undefined ? args[2] : null);
-      const parsedBeforeTurn = Number(beforeTurnRaw);
+      const parsedBeforeTurn = typeof beforeTurnRaw === 'number'
+        ? beforeTurnRaw
+        : typeof beforeTurnRaw === 'string' && beforeTurnRaw.trim()
+          ? Number(beforeTurnRaw)
+          : null;
       const beforeTurn = Number.isInteger(parsedBeforeTurn) && parsedBeforeTurn >= 0 ? parsedBeforeTurn : null;
       const parsedLimit = Number(stdinData?.limit ?? args[3]);
       const limit = Number.isInteger(parsedLimit) && parsedLimit > 0 ? Math.min(parsedLimit, 200) : 30;