Add config API and settings UI

GET/PUT /api/config for pay dates and amounts.
Settings page fetches and saves configuration.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

server/src/index.js

@@ -3,6 +3,7 @@ const express = require('express');
 const cors = require('cors');
 const path = require('path');
 const healthRouter = require('./routes/health');
+const configRouter = require('./routes/config');
 const db = require('./db');
 
 const app = express();
@@ -13,6 +14,7 @@ app.use(express.json());
 
 // API routes
 app.use('/api', healthRouter);
+app.use('/api', configRouter);
 
 // Serve static client files in production
 const clientDist = path.join(__dirname, '../../client/dist');

server/src/routes/config.js

@@ -0,0 +1,82 @@
+const express = require('express');
+const router = express.Router();
+const { pool } = require('../db');
+
+const CONFIG_KEYS = [
+  'paycheck1_day',
+  'paycheck2_day',
+  'paycheck1_gross',
+  'paycheck1_net',
+  'paycheck2_gross',
+  'paycheck2_net',
+];
+
+const DEFAULTS = {
+  paycheck1_day: 1,
+  paycheck2_day: 15,
+};
+
+async function getAllConfig() {
+  const result = await pool.query(
+    'SELECT key, value FROM config WHERE key = ANY($1)',
+    [CONFIG_KEYS]
+  );
+
+  const map = {};
+  for (const row of result.rows) {
+    map[row.key] = row.value;
+  }
+
+  const config = {};
+  for (const key of CONFIG_KEYS) {
+    const raw = map[key] !== undefined ? map[key] : (DEFAULTS[key] !== undefined ? String(DEFAULTS[key]) : null);
+    config[key] = raw !== null ? Number(raw) : null;
+  }
+
+  return config;
+}
+
+router.get('/config', async (req, res) => {
+  try {
+    const config = await getAllConfig();
+    res.json(config);
+  } catch (err) {
+    console.error('GET /api/config error:', err);
+    res.status(500).json({ error: 'Failed to fetch config' });
+  }
+});
+
+router.put('/config', async (req, res) => {
+  try {
+    const updates = req.body;
+    const validKeys = Object.keys(updates).filter((k) => CONFIG_KEYS.includes(k));
+
+    if (validKeys.length > 0) {
+      const client = await pool.connect();
+      try {
+        await client.query('BEGIN');
+        for (const key of validKeys) {
+          await client.query(
+            `INSERT INTO config (key, value) VALUES ($1, $2)
+             ON CONFLICT (key) DO UPDATE SET value = EXCLUDED.value`,
+            [key, String(updates[key])]
+          );
+        }
+        await client.query('COMMIT');
+      } catch (err) {
+        await client.query('ROLLBACK');
+        throw err;
+      } finally {
+        client.release();
+      }
+    }
+
+    const config = await getAllConfig();
+    res.json(config);
+  } catch (err) {
+    console.error('PUT /api/config error:', err);
+    res.status(500).json({ error: 'Failed to update config' });
+  }
+});
+
+module.exports = router;