[TT-1601] More flexible gas estimation

[Tofel]

Scope:

• allow to disable congestion metrics, when using automated gas estimations, by setting gas_price_estimation_blocks to 0. Rationale? more flexibility, avoiding rate limiting on RPC endpoints until configuration that allows to limit call concurrency is introduced
• change default gas price: 1 gwei -> 100 gwei to avoid stuck transactions in live networks on RPC health-check
• fix how Stats work by calculating from block number instead of using block count; if gas_price_estimation_blocks is set to 0 use 100 blocks

Tests:

• use live RPC with gas_price_estimation_blocks set to 0 and still get valid gas estimations

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Below is a summarization created by an LLM (gpt-4-0125-preview). Be mindful of hallucinations and verify accuracy.

Why

The changes improve the gas price estimation logic and adjust the default gas price settings to better align with current network conditions. It also fine-tunes the behavior of gas estimation based on network congestion and provides clearer logging for developers.

What

• README.md: Enabled gas price estimations by changing WithGasPriceEstimations from false to true. This change allows the client to automatically adjust gas prices based on network activity.
• README.md: Clarified the behavior of gas price estimation during network congestion, including how congestion analysis is disabled if gas_price_estimation_blocks equals 0.
• README.md: Updated the description for fee selection to use the greatest of node's suggested tip or the historical average tip, improving the accuracy of gas price estimations.
• README.md: Specified that if gas_price_estimation_blocks is higher than 0, gas prices are adjusted based on congestion rate, enhancing the detail provided on how gas prices are modified.
• client.go: Modified log message in ValidateConfig when gas estimation is enabled but block headers to use is set to 0. This change makes the log message more informative by explaining the impact on gas estimation.
• config.go: Increased the default gas price from 1 Gwei to 100 Gwei, reflecting changes in network conditions to ensure transactions are competitive.
• gas.go: Added logic to set a default starting block number for gas estimation if the current block number is greater than 100, ensuring there's a fallback mechanism for gas estimation.
• gas_adjuster.go: Added checks to skip congestion metric calculations if GasPriceEstimationBlocks is 0, optimizing performance and clarifying when congestion adjustments apply.

[skudasov]

Implicit, should we add this to docs that we'll use the last 100 blocks if no fromNumber was specified?

[Tofel]

good idea, added

[cl-sonarqube-production]

Quality Gate failed

Failed conditions
12.5% Duplication on New Code (required ≤ 3%)

See analysis details on SonarQube