feat(txmanager): add custom error for nil ctx provider

[gonnafaraway]

What problem does this PR solve?

Creates specific error for cases where ctx provider is nil.

Issue Number: ref #46039

Problem Summary:

What is changed and how it works?

Adds new error type for nil context provider.

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No code

Side effects

• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Breaking backward compatibility

Documentation

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Changes MySQL compatibility

Release note

Please refer to Release Notes Language Style Guide to write a quality release note.

None

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[ti-chi-bot]

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[ti-chi-bot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

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Once this PR has been reviewed and has the lgtm label, please assign 3pointer, benjamin2037, easonn7, lance6716, tiancaiamao, wjhuang2016, zanmato1984 for approval. For more information see the Kubernetes Code Review Process.

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[gonnafaraway]

Made rebase, check plz

[gonnafaraway]

@3pointer @Benjamin2037 @lance6716 check plz

[ti-chi-bot]

PR needs rebase.

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