fix(config): register takes.bootstrap_enabled too — same unregistered-key class

Hit while enabling the takes bootstrap on a live brain: the onboard
remediation's documented enable key fails 'Unknown config key' exactly like
auto_chronicle did. Registered + pinned by the same regression test.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FQgByq4aqQq2PP8UHCdnfk

src/core/config.ts

@@ -927,6 +927,10 @@ export const KNOWN_CONFIG_KEYS: readonly string[] = [
   // operator had to discover --force by reading source. Same class as the
   // spend-controls registration above.
   'auto_chronicle',
+  // Takes bootstrap (v0.41.18.0, A12). The onboard remediation's two-gate
+  // consent reads this key, and enabling it is the documented path to
+  // `gbrain takes extract --from-pages` — same unregistered-key class.
+  'takes.bootstrap_enabled',
   'sync.cost_gate_min_usd',
   'sync.federated_v2',
   'embed.backfill_cooldown_min',

test/config.test.ts

@@ -259,6 +259,8 @@ describe('KNOWN_CONFIG_KEYS — documented enable commands must be registered',
     const { KNOWN_CONFIG_KEYS, KNOWN_CONFIG_KEY_PREFIXES } = await import('../src/core/config.ts');
     // The flag the chronicle backstop reads (isAutoChronicleEnabled).
     expect(KNOWN_CONFIG_KEYS).toContain('auto_chronicle');
+    // The takes bootstrap two-gate consent flag (v0.41.18.0 A12).
+    expect(KNOWN_CONFIG_KEYS).toContain('takes.bootstrap_enabled');
     // chronicle.tz (chronicleTz) + future chronicle.* knobs.
     expect(KNOWN_CONFIG_KEY_PREFIXES.some(p => 'chronicle.tz'.startsWith(p))).toBe(true);
   });