[Feat] add db alert

[tanut32039]

Fixed: #XXXX

Implementation details

• add alert when failed saving database transaction

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[Copilot]

Pull Request Overview

This PR adds database transaction failure alerting capabilities to the EVM relayer. The changes refactor transaction handling to introduce alert mechanisms that trigger when database operations fail, including when fetching block information, getting balance data, or saving transactions to the database.

Key changes:

• Consolidated NewUnconfirmedTransaction and NewConfirmedTransaction into a single NewTransaction function
• Removed TxHash field from TxResult structure (redundant as it's passed separately)
• Added three new alert types: GetBlockErrorMsg, GetBalanceErrorMsg, and SaveDatabaseErrorMsg
• Refactored transaction saving logic into prepareTransaction and handleSaveTransaction helper functions with integrated alerting

Reviewed Changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 7 comments.

Show a summary per file

File	Description
relayer/alert/alert.go	Adds three new alert message constants for database-related errors
relayer/db/types.go	Changes BlockTimestamp to nullable pointer type and consolidates transaction constructor functions
relayer/chains/evm/types.go	Removes redundant TxHash field from TxResult struct and its constructor
relayer/chains/evm/provider.go	Refactors transaction preparation and saving with integrated alert triggering/resetting for database operations
relayer/chains/evm/provider_test.go	Updates test expectations to reflect removed TxHash parameter
relayer/chains/evm/provider_legacy_test.go	Removes GetBalance mock expectations since balance fetching is now conditional on database presence
relayer/chains/evm/provider_eip1559_test.go	Removes GetBalance mock expectations since balance fetching is now conditional on database presence

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[Copilot]

Pull Request Overview

Copilot reviewed 7 out of 7 changed files in this pull request and generated no new comments.

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[Copilot]

Pull Request Overview

Copilot reviewed 7 out of 7 changed files in this pull request and generated 2 comments.

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