feat: add Tool Search domain restriction bypass with active-installation patching

Resolve the active `claude` command from PATH and apply an equal-length
byte patch to remove the domain whitelist check. Backups are stored in
~/.cc-switch/toolsearch-backups/ (SHA-256 of path) so they survive
Claude Code version upgrades. The patch auto-reapplies on app startup
when the setting is enabled.

Frontend checks PatchResult.success and rolls back the setting on failure.

src/hooks/useSettingsForm.ts

@@ -85,6 +85,7 @@ export function useSettingsForm(): UseSettingsFormResult {
         data.enableClaudePluginIntegration ?? false,
       silentStartup: data.silentStartup ?? false,
       skipClaudeOnboarding: data.skipClaudeOnboarding ?? false,
+      toolSearchBypass: data.toolSearchBypass ?? false,
       claudeConfigDir: sanitizeDir(data.claudeConfigDir),
       codexConfigDir: sanitizeDir(data.codexConfigDir),
       geminiConfigDir: sanitizeDir(data.geminiConfigDir),
@@ -107,6 +108,7 @@ export function useSettingsForm(): UseSettingsFormResult {
             minimizeToTrayOnClose: true,
             enableClaudePluginIntegration: false,
             skipClaudeOnboarding: false,
+            toolSearchBypass: false,
             language: readPersistedLanguage(),
           } as SettingsFormState);
 
@@ -143,6 +145,7 @@ export function useSettingsForm(): UseSettingsFormResult {
           serverData.enableClaudePluginIntegration ?? false,
         silentStartup: serverData.silentStartup ?? false,
         skipClaudeOnboarding: serverData.skipClaudeOnboarding ?? false,
+        toolSearchBypass: serverData.toolSearchBypass ?? false,
         claudeConfigDir: sanitizeDir(serverData.claudeConfigDir),
         codexConfigDir: sanitizeDir(serverData.codexConfigDir),
         geminiConfigDir: sanitizeDir(serverData.geminiConfigDir),