Child bounties module e2e tests (#409)

* childBounties added for kusama

* childBounties added for polkadot

* update import

* childBounties added

* helper functions added for child bounties

* childBounties creation test added

* setStorage lastSpendPeriod such that next spend is few blocks ahead

* devAccounts replaced with testAccounts

* sendTransation modularized

* assigning and accepting a child bounty curator test added

* awarding and claiming a child bounty test added

* test added : closure and payout of a child bounty

* test added: rejection and cancellation of a child bounty

* failure test parent bounty not active error added

* failure test insufficient bounty balance error test added

* failure test child bounty with invalid value error added

* failure test invalid child bounty curator fee added

* failure test accept curator when child bounty is in added state added

* failure test close child bounty in pending payout status added

* refac: success and failure tests are grouped

* kusama snapshot for childBounties added

* snapshot for childBounties for polkadot added

* refac

* unassign curator different cases test added

* child bounty storage verification test added

* added setLastSpendPeriodBlockNumber fn for repeated logic

* added extractExtrinsicFailedEvent() for repeated logic

* minor improvements

* snapshot updated for childBounties

* linter warning fixed

* linter warning fixed

* testAccountBalance set as a multiple of exential deposit

* test docs improved and some tests renamed for better clarity

* additional checks added in childBountyCreationTest

* test added: non-curator trying to create child bounty throws `RequireCurator` error

* test added: parent already has `MaxActiveChildBountyCount` child bounties, trying to create a new one throws `TooManyChildBounties` error

* test added: child bounty description larger than `MaximumReasonLength` throws `ReasonTooBig` error

* test added: proposing curator for invalid child bounty index throws `InvalidIndex` error

* lint fix

* snapshots updated

* ts docs updated

* child bounties e2e tests added in readme

* Add Kusama AH childBounties E2E tests

* Port child bounties E2E tests to Kusama AH

* fix tests on KAH and added additional status checks

* snaps updated

* testConfig for child bounties for polkadot updated

* child bounties removed form Kusama relay

* child_bounties renamed to childBounties

* testConfig specified

* count added for multiple new blocks

* unassign curator test separated into separate tests

* refac the unassign tests with helper function

* snaps updated

* empty snapshot events fixed

* tests delineated into sections

* refactored with hepler function and delineate tests

Author: dhirajs0

README.md

@@ -154,6 +154,18 @@ These include:
     - Bounty closure restrictions (approved/pending payout states)
     - Non-curator attempting to accept curator role
     - Child bounty constraints preventing parent bounty closure
+- E2E test suite for child bounties infrastructure:
+  - Child bounty creation, curator assignment, acceptance, awarding and claiming workflows
+  - Child bounty closure and fund return to parent bounty
+  - Child bounty rejection by curators and cancellation by parent curators
+  - Curator unassignment scenarios with different deposit handling (refund vs. slash)
+  - Storage verification for child bounty counters and cleanup
+  - Comprehensive failure mode testing:
+    - Creating child bounties from non-active parent bounties
+    - Child bounty with InvalidValue, InvalidIndex, InvalidFee, TooManyChildBounties, ReasonTooBig
+    - Accepting curators in wrong child bounty states
+    - Closing child bounties in pending payout status
+    - Non-curator attempting to create child bounties
 
 The intent behind these end-to-end tests is to cover the basic behavior of relay chains' and system
 parachains' runtimes.