refactor: modify tests to inject minimum app

[cloudgray]

Description

Closes: #832

• Provide a minimal, copy‑friendly evmd/app skeleton that only wires the foundational keepers so third‑party chain developers can drop it into their projects without carrying the full Cosmos SDK scaffolding.
• All of the extra keepers, precompiles, and test‑only plumbing that our existing suites rely on now live in lightweight wrappers tailored to each test harness; the wrappers layer their custom wiring on top of the base app before injecting it into the suites.

Consideration

• The reason why test code coverage is lower than before is because werc20 precompile tests were removed. I didn't handled werc20 precompile tests because it will be removed. (#808)

---

Author Checklist

All items are required. Please add a note to the item if the item is not applicable and
please add links to any relevant follow up issues.

I have...

• tackled an existing issue or discussed with a team member
• left instructions on how to review the changes
• targeted the main branch

[vladjdk]

@cloudgray there are some conflicts

[github-actions]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed in 7 days-before-close if no further activity occurs.

[github-actions]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed in 7 days-before-close if no further activity occurs.