Do not suggest element names you define in the for directive element

[xterao]

When performing code completion within a for directive block, the element names you define yourself are also suggested.
Elements within the same for directive are excluded.

[Copilot]

Pull Request Overview

This PR aims to improve SQL code completion by ensuring that element names defined within a for directive block are not redundantly suggested during code completion.

• Test case updated to cover additional suggestions including "member" and a special token "%for".
• The for directive item retrieval now uses a primary expression rather than an identifier.
• Filtering logic in the parameter completion provider is refined to exclude items from the current for directive context.

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
src/test/kotlin/org/domaframework/doma/intellij/complate/sql/SqlCompleteTest.kt	Updated expected suggestion list to include extra element names for a more complete test of for directive exclusion.
src/main/kotlin/org/domaframework/doma/intellij/extension/psi/SqlElForDirectiveExtension.kt	Changed retrieval from SqlElIdExpr to SqlElPrimaryExpr to better capture the intended for directive item.
src/main/kotlin/org/domaframework/doma/intellij/contributor/sql/provider/SqlParameterCompletionProvider.kt	Modified logic to filter out for directive items that belong to the current context, preventing self-suggestion.

Comments suppressed due to low confidence (3)

src/test/kotlin/org/domaframework/doma/intellij/complate/sql/SqlCompleteTest.kt:292

• Ensure that additional test cases are added to verify that element names defined within a for directive are properly excluded from code completion suggestions.

listOf("employee", "member", "%for")

src/main/kotlin/org/domaframework/doma/intellij/contributor/sql/provider/SqlParameterCompletionProvider.kt:369

• [nitpick] Consider adding a brief comment explaining the rationale behind filtering out for directive items that match the current context, to aid future maintainers.

val parentForDirectiveExpr = PsiTreeUtil.getParentOfType(position, SqlElForDirective::class.java) ?: PsiTreeUtil.getChildOfType(position.parent, SqlElForDirective::class.java)

src/main/kotlin/org/domaframework/doma/intellij/extension/psi/SqlElForDirectiveExtension.kt:34

• Confirm that switching from SqlElIdExpr to SqlElPrimaryExpr correctly returns the intended for directive item without affecting downstream logic.

.getChildOfType(this, SqlElPrimaryExpr::class.java)