calculate user visit count and save to redis

[tingyuchang]

這個 PR 的目的 / Purpose of this PR

1. create collection user_visit
2. save user visit record when api check login
3. add cron job: calculate user visit each 10 mins and set to redis

相關的 issue / Related Issues

#263

TODO:

1. get user visit count from go-pttbbs
2. provide api return go-pttbbs + go-openbbsmiddleware user visit count
3. add prometheus

[codecov-commenter]

Codecov Report

Merging #333 (70e920c) into main (2fbb088) will decrease coverage by 0.17%.
The diff coverage is 35.00%.

@@            Coverage Diff             @@
##             main     #333      +/-   ##
==========================================
- Coverage   65.76%   65.59%   -0.18%     
==========================================
  Files         142      145       +3     
  Lines        6926     6966      +40     
==========================================
+ Hits         4555     4569      +14     
- Misses       1644     1667      +23     
- Partials      727      730       +3     

Impacted Files	Coverage Δ
api/api_login_required_path.go	0.00% <0.00%> (ø)
cron/calculate_user_visit.go	0.00% <0.00%> (ø)
main.go	0.00% <0.00%> (ø)
schema/user_visit_count.go	0.00% <0.00%> (ø)
schema/init.go	65.74% <66.66%> (+0.03%)	⬆️
schema/user_visit.go	71.42% <71.42%> (ø)

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[chhsiao1981]

1. Can you change schema/redis.go to schema/user_visit_count.go (like schema/lock.go)?
2. Can you have TIME_CALC_ALL_USER_VISIT_COUNTS = -10 * time.Minute in schema/const.go?

[chhsiao1981]

/lgtm