feat: E2E regression tests

[ptrus]

Closes: #775

[Copilot]

Pull Request Overview

This PR implements a comprehensive E2E regression testing framework for the oasis-web3-gateway, introducing automated testing of Web3 JSON-RPC endpoints against real blockchain data. The key changes include refactoring the source abstraction layer, adding pebble caching, and creating the testing infrastructure.

• Introduces a new source abstraction layer to centralize node communication
• Adds pebble-based caching for improved performance during testing and operation
• Implements a complete E2E regression testing framework with bash scripts and test suites

Reviewed Changes

Copilot reviewed 119 out of 123 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
source/*.go	New source abstraction layer providing unified interface for node and cached data access
tests/e2e_regression/	Complete testing framework with scripts, test cases, and expected outputs
main.go	Refactored application startup with proper service lifecycle management
rpc/, indexer/	Updated to use new source abstraction instead of direct client access
storage/psql/psql.go	Added log ordering for consistent test results

Comments suppressed due to low confidence (2)

tests/e2e_regression/run.sh:1

• Error handling is being ignored with the blank identifier. Consider logging errors or handling them appropriately in the test context.

#!/bin/bash

tests/e2e_regression/run.sh:1

• Error handling is being ignored with the blank identifier. Consider logging errors or handling them appropriately in the test context.

#!/bin/bash

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[Copilot]

Pull Request Overview

Copilot reviewed 119 out of 123 changed files in this pull request and generated 4 comments.

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