fix: orchestrator button + Pi SDK session error

- Move leftSidebarMode from URL state to local useState in unified-shell,
    avoiding force-dynamic router round-trip that made the button appear broken                                           - Replace fileURLToPath(new URL(..., import.meta.url)) with process.cwd()
    in bb-pi-bootstrap.ts — import.meta.url is a webpack:// URL in Next.js,
    causing cross-realm TypeError when passed to Node.js fileURLToPath()

src/tui/tools/bb-deviation.ts

@@ -0,0 +1,39 @@
+import { Type } from '@sinclair/typebox';
+import type { ToolDefinition } from '@mariozechner/pi-coding-agent';
+import { embeddedPiDaemon } from '../../lib/embedded-daemon';
+
+export function createDeviationTool(projectRoot: string): ToolDefinition {
+  return {
+    name: 'bb_record_deviation',
+    label: 'Record Template Deviation',
+    description: 'Log when and why you are deviating from a standard mission template (e.g., adding an extra worker, skipping an archetype, changing the flow).',
+    parameters: Type.Object({
+      reason: Type.String({ description: 'Why the deviation was necessary' }),
+      deviation_type: Type.String({ description: 'What kind of deviation (e.g., "extra_worker", "missing_archetype", "custom_flow")' }),
+      details: Type.Optional(Type.String({ description: 'Additional context about the deviation' })),
+    }),
+    async execute(_toolCallId, params: any) {
+      try {
+        // We use the existing daemon event system to record this
+        embeddedPiDaemon.appendEvent(projectRoot, {
+          kind: 'deviation.proposed',
+          title: `Deviation [${params.deviation_type}]`,
+          detail: params.reason,
+          status: 'idle',
+        });
+
+        return {
+          content: [{ type: 'text', text: 'Deviation recorded successfully.' }],
+          details: {},
+        };
+      } catch (error) {
+        const message = error instanceof Error ? error.message : String(error);
+        return {
+          content: [{ type: 'text', text: `Failed to record deviation: ${message}` }],
+          isError: true,
+          details: {},
+        };
+      }
+    },
+  };
+}