Hide competition until deadline passes

[fafk]

Description

Hides solver competition API data until the auction's submission deadline block has passed. Feature-gated via hide-competition-before-deadline (default off) to avoid breaking external solver monitoring that depends on these endpoints.

Changes

• Added hide-competition-before-deadline bool to orderbook config (default false)
• Wired CurrentBlockWatcher into AppState so handlers can check the current block
• Return 404 while deadline hasn't passed
• E2E test updated to exercise both the 404 and the post-deadline visibility

How to test

cargo test -p e2e 'solver_competition::local_node_solver_competition' -- --exact --ignored 

[gemini-code-assist]

Code Review

This pull request introduces a hide_competition_before_deadline configuration to restrict solver competition data visibility until the auction deadline is reached. Feedback identifies a performance issue in the V1 API implementation where an additional database query is executed per request, suggesting a join or DTO update instead. Additionally, a correction was suggested for error handling consistency when acquiring database connections in the new get_auction_deadline method.

[MartinquaXD]

LGTM.
Last nit: I think we should use <= block since the observed block already happened and revealing the information now can no longer affect the auction in question.

[fhenneke]

What is the plan for supporting the use case of the circuit breaker? The circuit breaker (ideally) needs to be able to check transactions right when they appear on chain. Waiting for the deadline or waiting for the autopilot to index a settlement correctly would be problematic at the moment.

[fafk]

What is the plan for supporting the use case of the circuit breaker? The circuit breaker (ideally) needs to be able to check transactions right when they appear on chain. Waiting for the deadline or waiting for the autopilot to index a settlement correctly would be problematic at the moment.

We can expose the data under a new endpoint protected by an API key.