Change wait condition to check for trades

[jmg-duarte]

Description

#4070 introduced some flakyness to the e2e test suite, this PR should fix that

Changes

• Re-organized the test order to make more sense when reading
• Changed the wait_for_condition to wait for a trade that has a tx_hash
• Mint blocks with the settlement wait condition

How to test

https://github.com/cowprotocol/services/actions/runs/21246964171/job/61138541511?pr=4079

 RUST_BACKTRACE=1 cargo nextest run -r -p e2e local_node_solver_competition_v1 --test-threads 1 --failure-output final --run-ignored ignored-only

[gemini-code-assist]

Code Review

The pull request addresses flakiness in e2e tests by refining the wait conditions and block minting strategy. The re-organization of test order also contributes to better readability. However, there are a couple of areas where the assumptions in the test code could be made more robust to prevent potential panics or unexpected behavior.