fix: switch lowering supports any number of cases (was capped at 8)

Replaced fixed-size locals (c0..c7) with O(n^2) linked-list walk
that handles arbitrary case counts via reverse-index traversal.
Added switch.bux test with 11 and 10 cases.

Makefile

@@ -5,7 +5,7 @@ BUILD_DIR := build
 # Project-local nimcache so CI can cache compiles (default is ~/.cache/nim).
 NIMFLAGS ?= --nimcache:nimcache
 
-EXAMPLES := hello fibonacci factorial structs enums methods algebraic_enums generics generics_struct generic_infer generic_infer2 extend_generic pattern_matching strings strings2 map result_option try_operator ownership ownership_checked ownership_release drop_early_return lifetime_elision ctfe ctfe_crc async concurrency os_time process json iter trait_bounds channel sync jwt stdlib_ergonomics tuples func_ptr map_remove array_iter_extra string_extra multi_closure iter_hof closure_control match_let string_interp iter_generic generic_infer_hof struct_tuple_pat match_block nested_patterns match_guards pattern_shadow move_field move_field_partial move_field_remaining move_field_nested move_field_ptr move_cross_fn c_precedence macro_twice macro_repeat macro_nested macro_hygiene macro_unhygienic macro_stmt_pat macro_tt macro_tt_raw macro_type collections_extra generic_enum
+EXAMPLES := hello fibonacci factorial structs enums methods algebraic_enums generics generics_struct generic_infer generic_infer2 extend_generic pattern_matching strings strings2 map result_option try_operator ownership ownership_checked ownership_release drop_early_return lifetime_elision ctfe ctfe_crc async concurrency os_time process json iter trait_bounds channel sync jwt stdlib_ergonomics tuples func_ptr map_remove array_iter_extra string_extra multi_closure iter_hof closure_control match_let string_interp iter_generic generic_infer_hof struct_tuple_pat match_block nested_patterns match_guards pattern_shadow move_field move_field_partial move_field_remaining move_field_nested move_field_ptr move_cross_fn c_precedence macro_twice macro_repeat macro_nested macro_hygiene macro_unhygienic macro_stmt_pat macro_tt macro_tt_raw macro_type collections_extra generic_enum switch
 
 # Platform smoke (macOS CI): full EXAMPLES still runs on Linux.
 EXAMPLES_SMOKE := hello ownership ownership_release strings map move_field move_field_partial move_field_remaining move_field_nested move_field_ptr move_cross_fn c_precedence macro_twice macro_repeat macro_nested macro_hygiene macro_unhygienic macro_stmt_pat macro_tt macro_tt_raw ctfe_crc

examples/switch.bux

@@ -0,0 +1,63 @@
+// switch.bux — Test switch with many cases (>8)
+
+import Std::Io::{PrintLine, PrintInt};
+
+func Main() -> int {
+    var x: int = 7;
+
+    switch x {
+        case 0:
+        PrintLine("zero");
+        case 1:
+        PrintLine("one");
+        case 2:
+        PrintLine("two");
+        case 3:
+        PrintLine("three");
+        case 4:
+        PrintLine("four");
+        case 5:
+        PrintLine("five");
+        case 6:
+        PrintLine("six");
+        case 7:
+        PrintLine("seven");
+        case 8:
+        PrintLine("eight");
+        case 9:
+        PrintLine("nine");
+        case 10:
+        PrintLine("ten");
+        default:
+        PrintLine("other");
+    }
+
+    // Test with match at end
+    x = 15;
+    switch x {
+        case 0:
+        PrintLine("a");
+        case 1:
+        PrintLine("b");
+        case 5:
+        PrintLine("c");
+        case 10:
+        PrintLine("d");
+        case 15:
+        PrintLine("fifteen-ok");
+        case 20:
+        PrintLine("e");
+        case 25:
+        PrintLine("f");
+        case 30:
+        PrintLine("g");
+        case 35:
+        PrintLine("h");
+        case 40:
+        PrintLine("i");
+        default:
+        PrintLine("default");
+    }
+
+    return 0;
+}

src/hir_lower.bux

@@ -3475,46 +3475,29 @@ module HirLower {
                 current = Lcx_LowerBlock(ctx, stmt.refStmtElse, -1);
             }
             // Cases in reverse order (from caseBlock)
+            // Walk linked list: count total, then for each i from total-1 down to 0,
+            // walk from start to find the i-th case. O(n²) but handles any count.
             if stmt.refStmtBlock != null as *Block {
                 let caseBlock: *Block = stmt.refStmtBlock;
-                var caseCount: int = caseBlock.stmtCount;
+                var total: int = 0;
-                // Collect cases into fixed-size locals for reverse iteration
-                var c0: *Stmt = null as *Stmt;
-                var c1: *Stmt = null as *Stmt;
-                var c2: *Stmt = null as *Stmt;
-                var c3: *Stmt = null as *Stmt;
-                var c4: *Stmt = null as *Stmt;
-                var c5: *Stmt = null as *Stmt;
-                var c6: *Stmt = null as *Stmt;
-                var c7: *Stmt = null as *Stmt;
-                var ci: int = 0;
                 var cs: *Stmt = caseBlock.firstStmt;
-                while cs != null as *Stmt && ci < 8 {
+                while cs != null as *Stmt {
-                    if ci == 0 { c0 = cs; }
+                    total = total + 1;
-                    if ci == 1 { c1 = cs; }
-                    if ci == 2 { c2 = cs; }
-                    if ci == 3 { c3 = cs; }
-                    if ci == 4 { c4 = cs; }
-                    if ci == 5 { c5 = cs; }
-                    if ci == 6 { c6 = cs; }
-                    if ci == 7 { c7 = cs; }
-                    ci = ci + 1;
                     cs = cs.nextStmt;
                 }
-                while caseCount > 0 {
+                var ri: int = total;
-                    caseCount = caseCount - 1;
+                while ri > 0 {
-                    var c: *Stmt = null as *Stmt;
+                    ri = ri - 1;
-                    if caseCount == 0 { c = c0; }
+                    // Find ri-th case by walking from start
-                    if caseCount == 1 { c = c1; }
+                    var i: int = 0;
-                    if caseCount == 2 { c = c2; }
+                    cs = caseBlock.firstStmt;
-                    if caseCount == 3 { c = c3; }
+                    while cs != null as *Stmt && i < ri {
-                    if caseCount == 4 { c = c4; }
+                        cs = cs.nextStmt;
-                    if caseCount == 5 { c = c5; }
+                        i = i + 1;
-                    if caseCount == 6 { c = c6; }
+                    }
-                    if caseCount == 7 { c = c7; }
+                    if cs != null as *Stmt {
-                    if c != null as *Stmt {
+                        let caseVal: *HirNode = Lcx_LowerExpr(ctx, cs.child1);
-                        let caseVal: *HirNode = Lcx_LowerExpr(ctx, c.child1);
+                        let caseBody: *HirNode = Lcx_LowerBlock(ctx, cs.refStmtBlock, -1);
-                        let caseBody: *HirNode = Lcx_LowerBlock(ctx, c.refStmtBlock, -1);
                         let cond: *HirNode = bux_alloc(sizeof(HirNode)) as *HirNode;
                         cond.kind = hBinary;
                         cond.intValue = 74;  // tkEq