Add article history by SKU and SSE update signals for live clients.

Expose getHistoryBySku as GET /article/:sku/history, and document mutation-emitted company signals via GET /events.

scripts/generateApiDocs.js

@@ -30,6 +30,7 @@ const options = {
         tags: [
             { name: 'Auth', description: 'Google SSO and session' },
             { name: 'Health', description: 'Connectivity checks' },
+            { name: 'Events', description: 'SSE update signals for live clients' },
             { name: 'Article', description: 'Articles under categories' },
             { name: 'Category', description: 'Category tree and membership' },
             { name: 'Company', description: 'Company CRUD' },
@@ -211,6 +212,16 @@ function renderOperation(apiPath, method, operation) {
         if (bodyLines) lines.push(...bodyLines);
     }
 
+    const signals = operation['x-signals'];
+    if (Array.isArray(signals) && signals.length) {
+        lines.push('## Signals');
+        lines.push('');
+        lines.push(
+            `On success, emits SSE signal${signals.length === 1 ? '' : 's'}: ${signals.map((s) => `\`${s}\``).join(', ')} (see [\`GET /events\`](../events.md)).`,
+        );
+        lines.push('');
+    }
+
     const responses = operation.responses || {};
     const successCodes = Object.keys(responses)
         .filter((c) => c.startsWith('2'))
@@ -305,6 +316,35 @@ function renderReadme(operations) {
     lines.push('');
     lines.push('Machine-readable spec: [`openapi.json`](openapi.json).');
     lines.push('');
+    lines.push('## Signals (SSE)');
+    lines.push('');
+    lines.push(
+        'Clients subscribe via [`GET /events`](routes/events.md) (`text/event-stream`). After a successful mutation, the API emits a named SSE event (signal) to subscribers of the same selected company.',
+    );
+    lines.push('');
+    lines.push('| Signal | Emitted by |');
+    lines.push('|--------|------------|');
+
+    /** @type {Map<string, string[]>} */
+    const bySignal = new Map();
+    for (const op of operations) {
+        const signals = spec.paths[op.path]?.[op.method]?.['x-signals'];
+        if (!Array.isArray(signals)) continue;
+        const label = `\`${op.method.toUpperCase()} ${op.path}\``;
+        for (const signal of signals) {
+            if (!bySignal.has(signal)) bySignal.set(signal, []);
+            bySignal.get(signal).push(label);
+        }
+    }
+    const signalNames = [...bySignal.keys()].sort();
+    if (signalNames.length === 0) {
+        lines.push('| — | _(none yet)_ |');
+    } else {
+        for (const signal of signalNames) {
+            lines.push(`| \`${signal}\` | ${bySignal.get(signal).join(', ')} |`);
+        }
+    }
+    lines.push('');
     lines.push('## DESIGN');
     lines.push('');
     lines.push('- for every route we have a file in  /src/api/routes');