feat: new ToolStarter component — unified workspace-first tool starting

- New ToolStarter component: workspace context, fetches real tool types,
  auto-fetches config profiles per tool type, shows SSH key status
- Backend: add repo_ssh_key_id to workspace list responses
- WorkspacesPage: uses ToolStarter in modal instead of StartToolModal
- WorkspaceDetailPage ToolsTab: uses ToolStarter in modal
- Removed old inline StartToolModal from workspace-detail.tsx
- Styles: .tool-starter-context, .context-row, .ssh-key-status

Quality gates: ruff clean, tsc --noEmit clean, pytest workspaces API (9 passed, 1 skipped)

apps/web/src/styles.css

@@ -5503,3 +5503,51 @@ a:active,
 	justify-content: flex-end;
 	margin-top: var(--space-2);
 }
+
+/* ─── Tool Starter ─── */
+.tool-starter {
+	display: flex;
+	flex-direction: column;
+	gap: var(--space-4);
+}
+
+.tool-starter-context {
+	background: var(--bg);
+	border: 1px solid var(--border);
+	border-radius: 10px;
+	padding: var(--space-3);
+	display: flex;
+	flex-direction: column;
+	gap: var(--space-2);
+}
+
+.context-row {
+	display: flex;
+	align-items: center;
+	gap: var(--space-3);
+	flex-wrap: wrap;
+}
+
+.context-label {
+	font-size: var(--font-size-sm);
+	color: var(--muted);
+	min-width: 80px;
+}
+
+.context-value {
+	font-weight: 500;
+}
+
+.ssh-key-status {
+	padding: var(--space-2);
+	background: var(--bg);
+	border-radius: 8px;
+}
+
+.ssh-key-status .success-text,
+.ssh-key-status .warning-text {
+	display: flex;
+	align-items: center;
+	gap: var(--space-2);
+	font-size: var(--font-size-sm);
+}