Fix transaction panics in endTransaction with "transaction not found"

[dsplayerX]

Purpose

Fixes https://github.com/ballerina-platform/module-ballerinai-transaction/issues/524 and ballerina-platform/ballerina-lang#41281

Goals

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Approach

Implemented essential locks when accessing the initiatedTransactions map to ensure concurrency safety.

User stories

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Release note

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Documentation

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Training

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Certification

Type “Sent” when you have provided new/updated certification questions, plus four answers for each question (correct answer highlighted in bold), based on this change. Certification questions/answers should be sent to certification@wso2.com and NOT pasted in this PR. If there is no impact on certification exams, type “N/A” and explain why.

Marketing

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Automation tests

• Unit tests

  Code coverage information

• Integration tests

  Transaction Concurrency Test available. This test assesses the concurrency of isolated tasks executing transactions concurrently, verifying they complete a specified number of transactions successfully.

Security checks

• Followed secure coding standards in http://wso2.com/technical-reports/wso2-secure-engineering-guidelines? yes/no
• Ran FindSecurityBugs plugin and verified report? yes/no
• Confirmed that this PR doesn't commit any keys, passwords, tokens, usernames, or other secrets? yes/no

Samples

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Related PRs

ballerina-platform/ballerina-lang#41506
ballerina-platform/ballerina-lang#41505
ballerina-platform/ballerina-lang#41504

Migrations (if applicable)

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Test environment

Tested on Ballerina 2201.8.0 and 2201.7.2.
Tested on Windows 10 19045.2006.

Learning

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[CLAassistant]

All committers have signed the CLA.

[codecov]

Codecov Report

Attention: 25 lines in your changes are missing coverage. Please review.

Comparison is base (2037cb9) 54.31% compared to head (ee909bf) 53.73%.

Files	Patch %	Lines
transaction-ballerina/commons.bal	52.17%	22 Missing ⚠️
transaction-ballerina/transaction_block.bal	57.14%	3 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##             master     #529      +/-   ##
============================================
- Coverage     54.31%   53.73%   -0.59%     
  Complexity       16       16              
============================================
  Files            22       22              
  Lines           672      683      +11     
  Branches        316      322       +6     
============================================
+ Hits            365      367       +2     
- Misses          306      315       +9     
  Partials          1        1              

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[github-actions]

This PR has been open for more than 15 days with no activity. This will be closed in 3 days unless the stale label is removed or commented.

[github-actions]

This PR has been open for more than 15 days with no activity. This will be closed in 3 days unless the stale label is removed or commented.

[rdulmina]

Shall we close this and reopen it when we start working on this again? @dsplayerX