IDLE: Add search to textview.ViewWindow

GitHub fields:

assignee = 'https://github.com/terryjreedy'
closed_at = None
created_at = <Date 2019-04-11.00:12:01.064>
labels = ['expert-IDLE', 'type-feature', '3.11']
title = 'IDLE: Add search to textview.ViewWindow'
updated_at = <Date 2022-02-23.04:09:44.039>
user = 'https://bugs.python.org/ShaneSmith'

bugs.python.org fields:

activity = <Date 2022-02-23.04:09:44.039>
actor = 'terry.reedy'
assignee = 'terry.reedy'
closed = False
closed_date = None
closer = None
components = ['IDLE']
creation = <Date 2019-04-11.00:12:01.064>
creator = 'Shane Smith'
dependencies = []
files = []
hgrepos = []
issue_num = 36595
keywords = ['patch']
message_count = 6.0
messages = ['339906', '339920', '348315', '348317', '358437', '413769']
nosy_count = 4.0
nosy_names = ['terry.reedy', 'Shane Smith', 'ZackerySpytz', 'fhackdroid']
pr_nums = ['17614']
priority = 'normal'
resolution = None
stage = 'patch review'
status = 'open'
superseder = None
type = 'enhancement'
url = 'https://bugs.python.org/issue36595'
versions = ['Python 3.11']