test: add update_rewards same epoch flow

[arad-starkware]

This change is 

---

Note

Adds a test ensuring update_rewards yields identical rewards when called twice within the same epoch (even after a block), and updates ideas accordingly.

• Tests:
  • Add update_rewards_same_epoch_flow_test in src/flow_test/test.cairo to assert rewards remain unchanged when calling update_rewards twice in the same epoch, including after advancing one block.
• Docs:
  • Update src/flow_test/flow_ideas.md by removing the corresponding test idea under update_rewards.
• Minor:
  • Small formatting tidy-up in a calculate_staker_strk_rewards_with_balances_v3 call.

^{Written by Cursor Bugbot for commit e4e5171. This will update automatically on new commits. Configure here.}

[arad-starkware]

Warning

This pull request is not mergeable via GitHub because a downstack PR is open. Once all requirements are satisfied, merge this PR as a stack on Graphite.
Learn more

• test: add update_rewards old delegator flow #94
• test: add update_rewards transition with balance change flow #93
• test: add update_rewards several blocks delegation rewards test #92
• test: add disable_rewards intermittently flow #91
• test: add update_rewards epoch length flow #90
• test: add update_rewards same epoch flow #89 👈 (View in Graphite)
• test: add update_rewards staker intent flow #88 : 1 other dependent PR (#95 )
• test: add update_rewards empty pools flow #87
• test: add update_rewards btc pools flow #86
• noa/staking/v3/rs-eic

This stack of pull requests is managed by Graphite. Learn more about stacking.

[noa-starkware]

Reviewable status: 0 of 2 files reviewed, 1 unresolved discussion (waiting on @arad-starkware)

---

src/flow_test/test.cairo line 3777 at r1 (raw file):

    let staker = system.new_staker(amount: stake_amount);
    let commission = 200;
    system.stake(:staker, amount: stake_amount, pool_enabled: false, :commission);

Please add strk delegate and btc delegate and test all the rewards