refactor: payment reconciliation tool (backport #27128)

[mergify]

Issue:
The problem with existing tool is that a user has to manually select invoices to reconcile against payments and, only one invoice can be reconciled against particular payment at a time which makes it tedious for the cases where multiple invoices are to be reconciled against single payment or vice versa

E.g. A single payment against multiple invoices
Suppose there are 50 invoices, a user will have to select an invoice against the payment 50 times and, GL Entry of this payment also gets cancelled & submitted 50 times

Fix:
Using this refactored tool, a user will be able to select any invoice or payment to reconcile.
Once the unreconciled entries are fetched, a user can either select any particular entries or just click on Allocate button without selecting anything, Allocation table will be populated based on FIFO and/or selection, and then click on Reconcile button to reconcile all the allocated entries.

• Added filter for payment transactions
• Created separate tables for payments & invoices
• Added new table 'Allocation'
• Minor UI clean-up
• Update docs

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This is an automatic backport of pull request #27128 done by [Mergify](https://mergify.com).

[mergify]

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On branch mergify/bp/version-13-hotfix/pr-27128
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Unmerged paths:
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	both modified:   erpnext/accounts/doctype/payment_reconciliation/payment_reconciliation.js
	both modified:   erpnext/accounts/doctype/payment_reconciliation/payment_reconciliation.json
	both modified:   erpnext/accounts/doctype/payment_reconciliation/payment_reconciliation.py
	both added:      erpnext/accounts/doctype/payment_reconciliation/test_payment_reconciliation.py
	both added:      erpnext/accounts/doctype/payment_reconciliation_allocation/payment_reconciliation_allocation.json
	both added:      erpnext/accounts/doctype/payment_reconciliation_allocation/payment_reconciliation_allocation.py
	both modified:   erpnext/accounts/utils.py
	both modified:   erpnext/controllers/accounts_controller.py

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