New global setting under /settings -> Interaction that controls the tool
approval flow:
auto (default) Skip every approval prompt — yolo. Matches --auto-approve.
prompt Built-in per-tool defaults only. Destructive tools (bash,
edit, write, eval, ssh) require confirmation; read-only
tools auto-allow; tools.approval.<tool> overrides ignored.
custom tools.approval.<tool> config wins. Built-in defaults only
fall back for tools the user hasn't configured. Critical
safety patterns (rm -rf /, fork bombs, curl|bash) still
prompt even when the tool is user-allowed.
The CLI --auto-approve / --yolo flag always wins regardless of the setting,
preserving the automation/CI path.
Wires through ExtensionToolWrapper.execute(): the wrapper reads
tools.approvalMode from settings, derives userPolicies only for custom mode,
and feeds the existing requiresApproval() resolver. Resolution order inside
requiresApproval already places user config above built-in defaults, so
'config wins' falls out naturally in custom mode.
Adds test/tools/approval-mode.test.ts covering all three modes, the CLI
override, the built-in fallback in custom mode, and the critical-pattern
override that fires even when bash is user-allowed.
