Revert "Derive with ranges" (#9964)

Reverts Z3Prover/z3#9963

src/ast/rewriter/seq_range_collapse.h

@@ -1,71 +0,0 @@
-/*++
-Copyright (c) 2026 Microsoft Corporation
-
-Module Name:
-
-    seq_range_collapse.h
-
-Abstract:
-
-    Recognize regexes that are boolean combinations of character-class
-    primitives (re.empty, re.full_char, re.range with concrete chars,
-    and re.union/inter/comp/diff over translatable arguments), and
-    materialize a seq::range_predicate back into a canonical regex AST.
-
-    Together with seq_rewriter integration, this lets any boolean
-    combination of character-class regexes collapse to a canonical
-    multi-range form, so that equivalent character classes share AST
-    identity, and downstream consumers (derivative, OneStep, caching)
-    can short-circuit them as pure range predicates.
-
-Authors:
-
-    Margus Veanes (veanes) 2026
-
---*/
-#pragma once
-
-#include "ast/rewriter/seq_range_predicate.h"
-#include "ast/seq_decl_plugin.h"
-
-namespace seq {
-
-    /**
-     * If r is a boolean combination of character-class regex primitives
-     * over the unsigned character domain [0, max_char], compute the
-     * equivalent range_predicate and return true. Otherwise return false
-     * with out untouched.
-     *
-     * Recognized fragment (all character-class-preserving operations):
-     *   re.empty                              -> empty
-     *   re.full_char_set                      -> top
-     *   re.range "c_lo" "c_hi"  (concrete)    -> [c_lo, c_hi]
-     *   re.union r1 r2                        -> p1 | p2
-     *   re.intersection r1 r2                 -> p1 & p2
-     *   re.diff r1 r2                         -> p1 - p2
-     *
-     * Notably re.complement is NOT recognized: it is a SEQUENCE-level
-     * complement (over all of Σ*), not a character-class complement, so
-     * collapsing it would change semantics whenever the result is used
-     * in any non-character-class context.  Sequence-level rewrites for
-     * re.complement (double-comp, deMorgan, etc.) are handled directly
-     * in seq_rewriter::mk_re_complement.
-     */
-    bool regex_to_range_predicate(seq_util& u, expr* r, range_predicate& out);
-
-    /**
-     * Canonical materialization of p as a regex AST over the given
-     * sequence sort. Two range_predicates with equal canonical
-     * representations produce structurally identical regex ASTs:
-     *
-     *   empty                  -> re.empty
-     *   top                    -> re.full_char_set
-     *   single range [lo, hi]  -> re.range "lo" "hi"
-     *   multiple ranges        -> right-associated re.union of single
-     *                              ranges, in increasing order of lo
-     *                              (matching the canonical range order
-     *                              held by range_predicate).
-     */
-    expr_ref range_predicate_to_regex(seq_util& u, range_predicate const& p, sort* seq_sort);
-
-}