feat: simplify AI chat architecture and add record links (#16463)

## Summary

This PR significantly simplifies the AI chat architecture by removing
complex routing/planning mechanisms and introduces clickable record
links in AI responses.

## Changes

### AI Chat Architecture Simplification
- **Removed** the entire `ai-chat-router` module (~850 lines) including:
  - Strategy decider service
  - Plan generator service
  - Complex routing logic
- **Removed** agent execution planning services (~700 lines):
  - `agent-execution.service.ts`
  - `agent-plan-executor.service.ts`
  - `agent-tool-generator.service.ts`
- **Added** centralized `ToolRegistryService` for tool management:
  - Builds searchable tool index (database, action, workflow tools)
  - Provides tool lookup by name
  - Supports agent search for loading expertise
- **Added** `ChatExecutionService` as simple replacement:
  - Includes full tool catalog in system prompt
- Pre-loads common tools (find/create/update for company, person,
opportunity, task, note)
  - Uses `load_tools` mechanism for dynamic tool activation
  - Enables native web search by default

### Record References in AI Responses
- Added `recordReferences` field to tool outputs for create, find, and
update operations
- Implemented `[[record:objectName:recordId:displayName]]` syntax for AI
to reference records
- Created `RecordLink` component that renders clickable chips with
object icons
- Integrated record link parsing into the markdown renderer
- Users can now click directly on created/found records in AI responses

### Workflow Agent Fixes
- Fixed cache invalidation issue when creating agents in workflows
- Added default prompt for workflow-created agents to prevent validation
errors
- Relaxed agent validation to only check properties being updated (not
all required properties)

### Code Quality Improvements
- Extracted `getRecordDisplayName` utility that mirrors frontend's
`getLabelIdentifierFieldValue` logic
- Uses object metadata to determine the correct label identifier field
- Handles `FULL_NAME` composite type for person/workspaceMember objects
- Shared across create, find, and update record services

## Net Impact
- **~1,200 lines deleted** (complex routing/planning code)
- **~500 lines added** (simpler tool registry + record links)
- Significantly reduced code complexity
- Better tool discovery through full catalog in system prompt
- Improved UX with clickable record references

## Testing
- Typecheck passes
- Lint passes
- Manual testing of AI chat with record creation and linking

packages/twenty-server/src/engine/core-modules/tool/types/tool-output.type.ts

@@ -1,3 +1,9 @@
+export type RecordReference = {
+  objectNameSingular: string;
+  recordId: string;
+  displayName: string;
+};
+
 export type ToolOutput<T = object> = {
   success: boolean;
   message: string;
@@ -6,4 +12,6 @@ export type ToolOutput<T = object> = {
   status?: number;
   statusText?: string;
   headers?: Record<string, string>;
+  // Record references for linking to created/found records
+  recordReferences?: RecordReference[];
 };