feat: set proposal's strategies fiat value

[wa0x6e]

Enhanced Proposal Voting Power Value Calculation

This PR implements comprehensive voting power value calculation for proposals by integrating with the Overlord service
to provide more accurate and precise strategy valuations.

Key Features

🎯 Core Enhancement:

• Add proposal strategy value fetching using Overlord service
• Store strategy values (vp_value_by_strategy) on proposal creation
• Implement precise decimal rounding (9 decimal places, from https://github.com/snapshot-labs/workflow/issues/618) for strategy values

🔧 Technical Improvements:

• New Module: src/helpers/entityValue.ts - Centralized fiat value logic
• Enhanced Proposal Creation: Fetch and store voting power values during proposal validation
• Precision Control: Consistent 9-decimal precision for strategy values across the system
• Error Handling: Robust error handling for Overlord service integration

⚠️ New behavior

• Proposal creation will fail on overlord error (mainly network issues and malformed strategies, should fallback to O otherwise)

🛠️ Code Quality:

• DRY Principle: Refactored JSON RPC request logic into reusable jsonRpcRequest utility
• Logging: Improved error logging and debugging capabilities

🔄 Refactoring:

• Extracted common JSON RPC patterns into shared utilities
• Improved error message consistency

Testing

• Create a new proposal, in a spaces with erc-20-balance-of strategies (+ other)
• The proposal should create successfully
• In the database, the vp_value_by_strategy column should contain an array of values: the token unit price of each strategy token, or 0 when unsupported. Array contains as many items as strategies
• On overlord service error (edit the url), proposal creation should fail

[Copilot]

Pull Request Overview

This PR enhances proposal voting power value calculation by integrating with the Overlord service to fetch and store precise strategy valuations during proposal creation.

• Implements fetching of strategy fiat values from Overlord service during proposal validation
• Stores strategy values in the vp_value_by_strategy database field with 9-decimal precision
• Refactors JSON RPC request logic into a reusable utility function

Reviewed Changes

Copilot reviewed 9 out of 10 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
src/writer/proposal.ts	Adds strategy value fetching during proposal verification and stores values in database
src/helpers/entityValue.ts	New module providing centralized strategy value calculation logic
src/helpers/utils.ts	Adds reusable jsonRpcRequest utility function
src/helpers/shutter.ts	Refactored to use new jsonRpcRequest utility
test/unit/writer/proposal.test.ts	Updates test expectations and mocks for new proposal verification behavior
test/integration/writer/proposal.test.ts	Updates integration tests to handle new action signature
test/integration/ingestor.test.ts	Adds mocking for entityValue module
package.json	Updates Node.js types dependency
.env.example	Adds new environment variable and fixes typo