fix: break long throws clauses one exception per line

[JebKJ21]

What changed with this PR:

Long throws clauses previously could not break and overflowed printWidth
(default 80). The throws printer now uses a conditionalGroup:

1. the whole exception list stays inline when it fits — no change to any
   currently-fitting output (full suite passes with only the overflowing
   cases regenerated), otherwise
2. exceptions print one per line, with throws kept attached to the
   parameter list — matching the formatting sketched in
   Improve formatting of method will lot of parameters and with exception #286 (comment)

Example

Input

class T {
  public void test() throws ExceptionOne, ExceptionTwo, ExceptionThree, ExceptionFour, ExceptionFive, ExceptionSix {}
}

Output

class T {
  public void test() throws
    ExceptionOne,
    ExceptionTwo,
    ExceptionThree,
    ExceptionFour,
    ExceptionFive,
    ExceptionSix {}
}

Relative issues or prs:

Fixes #286, closes #429. Supersedes #591, which targets the pre-tree-sitter
codebase and can no longer merge.

Verification

• All 226 unit tests pass; eslint, tsc, the self-format check, and a 5×
  idempotency run (update-test-output.js -times 5) are clean.
• Two-pass idempotency holds on the java-design-patterns corpus pinned by
  the e2e suite (tag 1.25.0, 1508 files) under both the previous and the
  new build; exactly 2 of those files change, both the intended fix
  (overflowing 97/84-char throws lines → one exception per line).

Note for maintainers: the $100 / $$ bug-bounty $$ labels currently sit on
#591 rather than on #286/#429 — could you confirm bounty eligibility for this
fix per https://www.jhipster.tech/bug-bounties/?