feat: add event block and agent GraphQL queries with tests

[jfrench9]

Summary

Implements GraphQL queries for event blocks and agents in the Ledger client, along with comprehensive test coverage for event block retrieval. This PR introduces the foundational data-fetching layer for interacting with the ledger's event block and agent entities.

Changes

New GraphQL Queries

• agent.ts – Query for fetching a single agent by identifier
• agents.ts – Query for fetching a paginated/filtered list of agents
• eventBlock.ts – Query for fetching a single event block
• eventBlocks.ts – Query for fetching multiple event blocks with filtering support

Client Layer

• LedgerClient.ts – Extended with new methods to execute agent and event block queries against the GraphQL API (106 new lines of client logic)

Generated Types

• graphql.ts – Updated generated GraphQL types to include the new query and response types for agents and event blocks (489 lines of generated schema types)

Tests

• LedgerClient.test.ts – Added 215 lines of test coverage focused on event block retrieval, including success paths, error handling, and edge cases

Key Details

• No UI/UX changes – This is a pure data-layer addition with no visual components affected.
• All new files – The 4 query files are net-new additions; the client, tests, and generated types are modifications to existing files.
• Total additions: 985 lines, no deletions — this is purely additive.

Breaking Changes

None. This PR only adds new queries and client methods without modifying existing interfaces or behavior.

Testing Notes for Reviewers

1. Unit tests – Review LedgerClient.test.ts for completeness of scenarios (single fetch, list fetch, error states, empty responses).
2. GraphQL query structure – Verify that the query fields in agent.ts, agents.ts, eventBlock.ts, and eventBlocks.ts align with the current ledger schema.
3. Generated types – Confirm graphql.ts was regenerated from the latest schema and that no manual edits were made to the generated file.
4. Integration consideration – While unit tests are included, reviewers should consider whether integration tests against a staging ledger endpoint are warranted before merging.

Browser Compatibility

No browser compatibility concerns — these changes are entirely server-side/client-layer GraphQL operations with no DOM, CSS, or browser API dependencies.

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🤖 Generated with Claude Code

Branch Info:

• Source: feature/event-block-graphql
• Target: main
• Type: feature

Co-Authored-By: Claude noreply@anthropic.com