[Bug][Compatibility]: Gitea cannot initialize because ALTER DATABASE COLLATE is rejected

## Description
Gitea/Gogs applications using MatrixOne through the MySQL protocol cannot complete ORM initialization because the collation bootstrap statement is rejected by the MatrixOne parser. This is observed in the `mo-scenario` integration deployment; MatrixOne service-component logs are not used as the source of this report.

## Environment
- MatrixOne cloud endpoint exposed through the MySQL protocol on port 6001
- Gitea integration image: `scenario-runner-gitea`
- Observed: 2026-09-16 (private `mo-scenario` cluster)

## Reproduction
Gitea executes the following MySQL-compatible statement during startup (database name abbreviated here):

```sql
ALTER DATABASE `gitea_mo`
CHARACTER SET utf8mb4 COLLATE utf8mb4_bin;
```

MatrixOne returns:

```text
Error 1064 (42000): SQL parser error
syntax error near " CHARACTER SET utf8mb4 COLLATE utf8mb4_bin"
```

The same error is emitted on every ORM initialization retry. The application eventually logs `InitDBEngine failed` and remains unready/enters CrashLoopBackOff.

## Expected behavior
Either accept the MySQL-compatible `ALTER DATABASE ... CHARACTER SET ... COLLATE ...` form, or provide a compatibility-safe no-op/response that allows the application migration to continue when the requested collation is already the effective collation. A supported MySQL application should not be blocked during startup by this statement.

## Impact
Gitea cannot start when configured to use MatrixOne, even though the database connection itself succeeds. This blocks deployment of the application without changing its source code or adding a dialect-specific workaround.

## Related
- #25103 tracks broader `information_schema` and migration-tool compatibility gaps.