feat(agents): consolidate connectors under mcp_discovery; route web search through google_search

MCP consolidation:
- Route all MCP-capable connectors (Slack, Jira, Linear, ClickUp, Airtable,
  Notion, Confluence, interim Gmail/Calendar, custom MCP) through a single
  `mcp_discovery` subagent. Drive/OneDrive/Dropbox stay native to enrich the KB.
- Deprecate Discord/Teams/Luma: no viable official MCP server.

Google-only web search:
- Remove the main-agent `web_search` tool and the SearXNG platform service;
  all public web search now flows through the `google_search` subagent via task().
- Deprecate the Tavily/SearXNG/Linkup/Baidu search connectors (HTTP 410 on
  create, "Deprecated" badge); guide heavy users to the custom MCP connector.
- Remove web search from anonymous chat (pure Q&A).
- Tear SearXNG out of docker compose + install scripts; drop tavily-python
  and linkup-sdk deps and their config/env vars.

Fix:
- metrics._package_version() now swallows any metadata lookup failure. A
  malformed editable-install distribution with no `Version` field raised
  KeyError deep in importlib.metadata, and since it runs on every
  record_subagent_invoke_duration call it was crashing every task()
  delegation. Verified end-to-end against live GPT-5.4.

Co-authored-by: Cursor <cursoragent@cursor.com>

surfsense_web/contracts/enums/toolIcons.tsx

@@ -11,7 +11,6 @@ import {
 	FolderPlus,
 	FolderTree,
 	FolderX,
-	Globe,
 	ImageIcon,
 	ListTodo,
 	type LucideIcon,
@@ -45,7 +44,6 @@ const TOOL_ICONS: Record<string, LucideIcon> = {
 	display_image: ImageIcon,
 	// Web / search
 	scrape_webpage: ScanLine,
-	web_search: Globe,
 	// Automations
 	create_automation: AlarmClock,
 	// Memory
@@ -149,7 +147,6 @@ const TOOL_DISPLAY_NAMES: Record<string, string> = {
 	display_image: "Show image",
 	// Web / search
 	scrape_webpage: "Read webpage",
-	web_search: "Search the web",
 	// Automations
 	create_automation: "Create automation",
 	// Memory