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A prefix/postfix increment or decrement (`x++`, `--x`, ...) is desugared into a block holding an induction temporary. The two frontends name that temporary differently: - K1 uses a per-scope counter, `tmp0`, `tmp1`, ... `tmpN`. - K2 uses the uniform special name `<unary>`. Decision: adopt the K2 name (`<unary>`) from both frontends. This is the only robust convergence direction: K1's counter-based `tmpN` numbering depends on the frontend's temporary allocation order and cannot be reproduced faithfully under K2 (mapping `<unary>` back to a single `tmp0` would wrongly collapse distinct temporaries such as `tmp0`..`tmp7` in one function). The uniform `<unary>` name is frontend-independent and identifies the construct just as well. (This supersedes the earlier D14 preference for the readable `tmpN` names, which was made before the numbering infeasibility was established.) Implementation: `extractBlock` recognises an `IrContainerExpression` whose origin is one of PREFIX_INCR / PREFIX_DECR / POSTFIX_INCR / POSTFIX_DECR and records its first statement (the induction temporary) together with the canonical name `<unary>`. `extractVariableExpr` emits that name for exactly that variable (matched by identity), leaving all other locals untouched. The recording is saved/restored around the block's statement extraction so nested blocks behave correctly. The detection is origin-based and therefore identical for K1 and K2. Full dual-suite relearn: all 3333 tests pass. The only changed rows are in test-kotlin1 (exprs/exprs, exprs/PrintAst, controlflow/basic/bbStmts and getASuccessor), where the K1 increment temporaries converge from `tmpN` to `<unary>`, matching K2. Remaining exprs.kt differences (unary-operand span, and the delegatedProperties `<set-?>`/`<get-x>` cluster) are separate location/naming items tracked elsewhere. The destructuring container temp (`tmp0_container` vs `<destruct>`) is handled separately in C14b. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>