Fix/coderabbit nits (#1259)

* fix: eliminate 8 as any in MCP handlers, structured output, and stream events

- Group A: Add : () => AnyObjectSchema type annotations to MCP notification
  schema constants (useIdeSelection, useIdeLogging, usePrompts, channelNotification)
- Group B: Add isStructuredOutputAttachmentMessage type guard for structured
  output attachment payloads (execAgentHook)
- Group C: Add isMessageDeltaStreamEvent type guard for message_delta
  stream event usage extraction (forkedAgent)

These as any casts also exist in the upstream CCB source — this fix provides
real type safety without changing any runtime behavior.

* feat: wire mode persona injection — Claude Soul Document distilled into system prompt

- prompts.ts: add getModePersonaSection() → injects current mode's
  systemPrompt as 'mode_persona' dynamic section (first in order,
  before operational instructions). Previously modes had systemPrompt
  fields but they were never sent to the model.
- modes/personas/claude.ts: 3KB distilled Claude persona from
  Anthropic's leaked Claude 4.5 Opus Soul Document (70KB → operational
  extract): core traits, 7 honesty principles, helpfulness/caution
  balance, collaboration stance, identity stability.
- With custom mode YAML (~/.claude/modes/claude.yaml), 7 modes total
  including the new Claude persona — fully operational at /mode claude.

Co-Authored-By: James Feng <47167674+GhostDragon124@users.noreply.github.com>

* fix: import path convention + reword persona source comment

- prompts.ts: use 'src/modes/store.js' alias instead of relative '../modes/store.js'
  to match the file's existing import convention
- claude.ts: reword JSDoc to say 'based on publicly available reference document'
  instead of 'leaked', addressing CodeRabbit review concern

src/hooks/useIdeLogging.ts

@@ -3,9 +3,10 @@ import { logEvent } from 'src/services/analytics/index.js'
 import { z } from 'zod/v4'
 import type { MCPServerConnection } from '../services/mcp/types.js'
 import { getConnectedIdeClient } from '../utils/ide.js'
+import type { AnyObjectSchema } from '@modelcontextprotocol/sdk/server/zod-compat.js'
 import { lazySchema } from '../utils/lazySchema.js'
 
-const LogEventSchema = lazySchema(() =>
+const LogEventSchema: () => AnyObjectSchema = lazySchema(() =>
   z.object({
     method: z.literal('log_event'),
     params: z.object({
@@ -27,7 +28,7 @@ export function useIdeLogging(mcpClients: MCPServerConnection[]): void {
     if (ideClient) {
       // Register the log event handler
       ideClient.client.setNotificationHandler(
-        LogEventSchema() as any,
+        LogEventSchema(),
         notification => {
           const { eventName, eventData } = notification.params
           logEvent(