refactor: rename files to PascalCase components and kebab-case APIs (Task 4.4)

- Rename all component files to PascalCase matching exported names
- Move components into feature directories (git/, session/, project/, terminal/, workspace/, ui/, layout/)
- Rename all page files to PascalCase with Page suffix
- Rename all API files to kebab-case
- Update all imports across codebase with corrected relative depths
- Preserve git history via git mv

Quality gates: tsc (pass), eslint (pass), 66/74 tests pass (8 pre-existing failures)
Refs: repo-restructure Task 4.4

apps/web/src/components/features/settings/SettingsTabLayout.tsx

@@ -0,0 +1,46 @@
+import React from "react";
+import { Link, useLocation } from "react-router-dom";
+import styles from "./features/settings/SettingsTabLayout.module.css";
+
+interface Tab {
+	id: string;
+	label: string;
+	path: string;
+}
+
+interface SettingsTabLayoutProps {
+	tabs: Tab[];
+	children: React.ReactNode;
+	basePath: string;
+}
+
+export const SettingsTabLayout: React.FC<SettingsTabLayoutProps> = ({
+	tabs,
+	children,
+	basePath,
+}) => {
+	const location = useLocation();
+
+	return (
+		<div className={styles.settingsLayout}>
+			<aside className={styles.settingsSidebar}>
+				<nav className={styles.settingsNav}>
+					{tabs.map((tab) => (
+						<Link
+							key={tab.id}
+							to={`${basePath}/${tab.path}`}
+							className={`${styles.settingsNavLink} ${
+								location.pathname.includes(tab.path)
+									? styles.settingsNavLinkActive
+									: ""
+							}`}
+						>
+							{tab.label}
+						</Link>
+					))}
+				</nav>
+			</aside>
+			<main className={styles.settingsContent}>{children}</main>
+		</div>
+	);
+};