refactor: stock balance report

[rohitwaghchaure]

Why refactor?

For the large db the stock balance report was not generating even though prepared report and the state was remaining in the Queued state and it was never completing

Investigation

During investigation, we found that if the user has not set item or warehouse filters then this issue happens. System fetch all the stock ledger entries to calculate the Opening Quantity and Opening Stock Value. If the number of stock ledger entries are more than 1 million and multiple users try to access the stock balance report without filters then RAM gets consumed fully and get the error "Work-horse was terminated unexpectedly (waitpid returned 15)".

New Changes

1. "Closing Stock Balance"

Added new doctype "Closing Stock Balance" to avoid calculation of Opening Quantity and Opening Stock Value. If you have closed the period then create the Closing Stock Balance for that period so that while preparing the stock balance report system will use the data of Closing Stock Balance and avoid Opening Quantity and Opening Stock calculations.

2. Changed IN clause with JOIN

While watching process log we have found that one query is taking time and that was item_code in () (see below image).
The IN operator works slowly if the number of data is huge and it's better to use join query

Profiling Result

Before Change

After Change

[codecov]

Codecov Report

Merging #35348 (3f548ac) into develop (3940deb) will decrease coverage by 0.05%.
The diff coverage is 65.30%.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop   #35348      +/-   ##
===========================================
- Coverage    63.82%   63.77%   -0.05%     
===========================================
  Files          813      814       +1     
  Lines        60260    60456     +196     
===========================================
+ Hits         38460    38556      +96     
- Misses       21800    21900     +100     

Impacted Files	Coverage Δ
...ype/closing_stock_balance/closing_stock_balance.py	0.00% <0.00%> (ø)
...rpnext/stock/report/stock_balance/stock_balance.py	79.92% <77.11%> (-4.38%)	⬇️
...xt/stock/report/stock_analytics/stock_analytics.py	91.92% <87.50%> (-1.99%)	⬇️
...value/warehouse_wise_item_balance_age_and_value.py	91.96% <91.17%> (-0.63%)	⬇️
erpnext/stock/report/stock_ageing/stock_ageing.py	90.95% <100.00%> (ø)

... and 3 files with indirect coverage changes