[wadoon]

What

Pass 2 of the compiler-warning cleanup. This branch originally resolved the
90 javac lint warnings (84× deprecation, 3× this-escape, 2× rawtypes,
1× unchecked; 94 sites found in this worktree) in 20 key.core files — the
prover-core classes bound to the deprecated ImmutableArray API.

Per the campaign cleanup decision, ALL serial and this-escape fixes were
REMOVED from history, so what remains is:

• deprecation (84): narrow-scope @SuppressWarnings("deprecation") with
  a one-line rationale per site, in the prover-core classes bound to the
  deprecated org.key_project.util.collection.ImmutableArray API (successor
  ImmutableList). These classes expose ImmutableArray in
  public/protected signatures, fields and ctor parameters consumed across
  key.core/key.ncore and the tests — swapping the runtime type is not
  locally provably behavior-preserving, so the agreed policy applies
  (TermFactory 20, StatementBlock 13, ClashFreeSubst 12,
  JAbstractSortedOperator 9, Operator 8, Throws 6, …).
• rawtypes/unchecked (3): folded into existing narrow suppressions
  (ClashFreeSubst, OneStepSimplifier, TacletApp).
• tests (4 files): legacy ScriptLineParser/NamespaceSet/ImmutableArray
  exercised deliberately — suppressed at method scope.

4 commits total (head 51a8e0b3ef).

Verification

History was rebuilt by re-writing the offending commits without the
this-escape content: the 3 @SuppressWarnings("this-escape") annotations on
the StatementBlock ctors were removed (a per-commit pattern scan over the
rewritten history for serialVersionUID, @Serial, "this-escape",
"serial", transient is clean), and git diff of the old vs. new branch
heads over the 20 touched files shows only those 6 removed lines — every other
warning fix (deprecation, rawtypes, unchecked) is kept exactly as-is. No
behavioral changes.

Draft — part of the warning-cleanup stack (pass 2; bases cw-2-ui, ultimately
targeting #4001).

Commits carry Co-Authored-By: OpenCode (KIT Medium).