assistant2: Allow profiles to enable all context servers (#27847)

This PR adds a new `enable_all_context_servers` field to agent profiles
to allow them to enable all context servers without having to opt into
them individually.

The "Write" profile will now have all context servers enabled out of the
box.

Release Notes:

- N/A

assets/settings/default.json

@@ -637,6 +637,8 @@
     "profiles": {
       "ask": {
         "name": "Ask",
+        // We don't know which of the context server tools are safe for the "Ask" profile, so we don't enable them by default.
+        // "enable_all_context_servers": true,
         "tools": {
           "diagnostics": true,
           "fetch": true,
@@ -650,6 +652,7 @@
       },
       "write": {
         "name": "Write",
+        "enable_all_context_servers": true,
         "tools": {
           "bash": true,
           "batch-tool": true,