Fix: Exclude generator functions from convert-to-class suggestions

[Copilot]

Generator functions (function*) were incorrectly triggering the TS80002 diagnostic "This constructor function may be converted to a class declaration". This is incorrect because generator functions have special semantics that are incompatible with class constructors.

Problem:

function* gen() {}
gen.prototype.next = gen.prototype.next;
gen.prototype.return = gen.prototype.return;

The above code would incorrectly trigger the convert-to-class suggestion, even though generator functions cannot be meaningfully converted to classes.

Solution:
Added checks in the canBeConvertedToClass function to exclude generator functions by testing for FunctionFlags.Generator in both function declaration and function expression paths.

Changes:

• Modified src/services/suggestionDiagnostics.ts to exclude generator functions
• Added comprehensive test coverage for generator declarations, generator expressions, and mixed scenarios
• Verified that regular constructor functions continue to work correctly

Testing:

• All existing tests pass
• New tests verify generator functions don't trigger the diagnostic
• Regular constructor functions still correctly trigger the diagnostic when appropriate

Fixes #62056.

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[RyanCavanaugh]

Run npx hereby format and commit that

[Copilot]

Run npx hereby format and commit that

Ran npx hereby format - no formatting changes were needed as the code is already properly formatted.

[typescript-bot]

With 6.0 out as the final release vehicle for this codebase, we're closing all PRs that don't fit the merge criteria for post-6.0 patches. If you think this was a mistake and this PR fits the post-6.0 patch criteria, please post to the 6.0 iteration issue with details (specifically, which PR and which patch criteria it satisfies).

Next steps for PRs:

• For crash bugfixes or language service improvements, PRs are currently accepted at the typescript-go repo
• Changes to type system behavior should wait until after 7.0, at which point mainline TypeScript development will resume in this repository with the Go codebase
• Library file updates (lib.d.ts etc) continue to live in this repo or the DOM Generator repo as appropriate