SQLAlchemy compliance: audit parameter and SQL rendering edge cases

[laughingman7743]

Context

Parent issue: #736

DifficultParametersTest is deleted.
FetchLimitOffsetTest.test_limit_render_multiple_times and StringTest.test_dont_truncate_rightside remain skipped.
These cases exercise bind parameter names and repeated or nested SQL rendering.

Scope

• Audit unusual bind parameter names and paramstyle conversion.
• Verify that limit rendering remains stable when a statement is compiled more than once.
• Verify that string expressions do not truncate the right-hand operand.
• Split this issue before implementation if the failures have unrelated causes or require separate public behavior changes.

Acceptance criteria

• Tests that the dialect can support are re-enabled.
• Each remaining skip documents a confirmed Athena limitation.
• Compiler and formatter changes have focused unit tests.
• just lint passes.
• Athena tests are executed one target at a time with -n 1; compile-only tests are preferred when they prove the behavior.