feat(connect): dedicated Claude.ai / ChatGPT browser connect picker

- Replace single 'Connect to Claude / ChatGPT' button with a modal picker
  offering Claude.ai web, Claude Desktop, Codex CLI, and ChatGPT/GPT Actions.
- Add /oauth/connect-claude-ai backend route that redirects to Anthropic's
  official https://claude.ai/api/mcp/auth_callback OAuth callback.
- Update MCP callback result page with browser-specific instructions for
  Claude.ai web, Claude Desktop, ChatGPT/GPT Actions, and Codex CLI.
- Deploy new app and hermes images to K8s.

product/app/styles.css

@@ -751,3 +751,66 @@ body {
   text-align: center;
   min-height: 18px;
 }
+
+
+/* MCP client picker modal */
+.mcp-picker h3 {
+  margin: 0 0 6px;
+  font-size: 1.25rem;
+}
+
+.picker-subtitle {
+  color: var(--text-secondary);
+  font-size: 0.9rem;
+  margin: 0 0 20px;
+  line-height: 1.5;
+}
+
+.picker-option {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  gap: 16px;
+  padding: 16px;
+  border: 1px solid var(--border);
+  border-radius: var(--radius);
+  margin-bottom: 12px;
+  background: var(--background);
+}
+
+.picker-option:last-child {
+  margin-bottom: 0;
+}
+
+.picker-meta {
+  flex: 1;
+  min-width: 0;
+}
+
+.picker-title {
+  font-weight: 600;
+  font-size: 0.95rem;
+  margin-bottom: 4px;
+}
+
+.picker-desc {
+  color: var(--text-secondary);
+  font-size: 0.8rem;
+  line-height: 1.4;
+}
+
+.picker-option .btn {
+  white-space: nowrap;
+  padding: 8px 14px;
+  font-size: 0.85rem;
+}
+
+.token-box {
+  background: var(--background);
+  border: 1px solid var(--border);
+  border-radius: var(--radius);
+  padding: 12px;
+  font-family: 'SF Mono', monospace;
+  font-size: 0.85rem;
+  word-break: break-all;
+}