feat: enable Remote Control (BRIDGE_MODE) with stub completions

- Add BRIDGE_MODE to DEFAULT_FEATURES in dev.ts
- Implement peerSessions.ts: cross-session messaging via bridge API
- Implement webhookSanitizer.ts: redact secrets from webhook payloads
- Replace any stubs in controlTypes.ts with Zod schema-inferred types
- Fix tengu_bridge_system_init default to true for app "active" status

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/bridge/peerSessions.ts

@@ -1,3 +1,73 @@
-// Auto-generated stub — replace with real implementation
-export {};
-export const postInterClaudeMessage: (target: string, message: string) => Promise<{ ok: boolean; error?: string }> = () => Promise.resolve({ ok: false });
+import axios from 'axios'
+import { logForDebugging } from '../utils/debug.js'
+import { errorMessage } from '../utils/errors.js'
+import { getReplBridgeHandle } from './replBridgeHandle.js'
+import { toCompatSessionId } from './sessionIdCompat.js'
+
+/**
+ * Send a plain-text message to another Claude session via the bridge API.
+ *
+ * Called by SendMessageTool when the target address scheme is "bridge:".
+ * Uses the current ReplBridgeHandle to derive the sender identity and
+ * the session ingress URL for the POST request.
+ *
+ * @param target - Target session ID (from the "bridge:<sessionId>" address)
+ * @param message - Plain text message content (structured messages are rejected upstream)
+ * @returns { ok: true } on success, { ok: false, error } on failure. Never throws.
+ */
+export async function postInterClaudeMessage(
+  target: string,
+  message: string,
+): Promise<{ ok: boolean; error?: string }> {
+  try {
+    const handle = getReplBridgeHandle()
+    if (!handle) {
+      return { ok: false, error: 'Bridge not connected' }
+    }
+
+    if (!target) {
+      return { ok: false, error: 'No target session specified' }
+    }
+
+    const compatTarget = toCompatSessionId(target)
+    const from = toCompatSessionId(handle.bridgeSessionId)
+    const baseUrl = handle.sessionIngressUrl
+
+    const url = `${baseUrl}/v1/sessions/${compatTarget}/messages`
+
+    const response = await axios.post(
+      url,
+      {
+        type: 'peer_message',
+        from,
+        content: message,
+      },
+      {
+        headers: {
+          'Content-Type': 'application/json',
+          'anthropic-version': '2023-06-01',
+        },
+        timeout: 10_000,
+        validateStatus: (s: number) => s < 500,
+      },
+    )
+
+    if (response.status === 200 || response.status === 204) {
+      logForDebugging(
+        `[bridge:peer] Message sent to ${compatTarget} (${response.status})`,
+      )
+      return { ok: true }
+    }
+
+    const detail =
+      typeof response.data === 'object' && response.data?.error?.message
+        ? response.data.error.message
+        : `HTTP ${response.status}`
+    logForDebugging(`[bridge:peer] Send failed: ${detail}`)
+    return { ok: false, error: detail }
+  } catch (err: unknown) {
+    const msg = errorMessage(err)
+    logForDebugging(`[bridge:peer] postInterClaudeMessage error: ${msg}`)
+    return { ok: false, error: msg }
+  }
+}