feat(gb32960): isolate per-block parse failures in body parser

主循环改造：单信息块 parser 抛 DecodeException / BufferUnderflowException /
IndexOutOfBoundsException 时不再放弃整帧。

- 固定长度块（fixedLen≥0）：回滚 reader，按 fixedLen 截取字节兜成 InfoBlock.Raw，
  position 前进 fixedLen，continue 循环继续解析后续块
- 变长块（fixedLen=-1）或剩余不足 fixedLen：剩余字节全部兜成 Raw 后 break
- parser 契约违反（consumed != declared fixedLen）仍抛异常，以暴露 parser bug，
  不走 lenient 兜底，避免静默误解析长期误判
- 仅捕获 DecodeException / BufferUnderflowException / IndexOutOfBoundsException，
  RuntimeException 继续向上抛，保留程序 bug 可见性
- 通过 lingniu.ingest.gb32960.parse.lenientBlockFailure=false 可回退严格模式

不改 InfoBlock.Raw record 结构；下游 Gb32960EventMapper 按 findBlock(Class) 类型
查找，新增 Raw 不影响业务事件映射。

Gb32960BodyParserIsolationTest 4/4 绿；全模块 39 tests 全绿，无回归。

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

protocol-gb32960/src/main/java/com/lingniu/ingest/protocol/gb32960/codec/Gb32960BodyParser.java

@@ -141,14 +141,57 @@ public final class Gb32960BodyParser {
 
             int fixedLen = parser.fixedLength();
             int posBefore = body.position();
+
+            // 预检：固定长度块在剩余字节不足时，lenient 模式兜 Raw 后 break；严格模式保持旧行为抛异常。
             if (fixedLen >= 0 && body.remaining() < fixedLen) {
-                throw new DecodeException(
-                        "info block 0x" + Integer.toHexString(typeCode)
-                                + " needs " + fixedLen + " bytes but got " + body.remaining());
+                if (!lenientBlockFailure) {
+                    throw new DecodeException(
+                            "info block 0x" + Integer.toHexString(typeCode)
+                                    + " needs " + fixedLen + " bytes but got " + body.remaining());
+                }
+                int remaining = body.remaining();
+                byte[] tail = new byte[remaining];
+                body.get(tail);
+                log.warn("[gb32960] truncated block typeCode=0x{} declaredFixedLen={} remaining={} — wrapping tail as Raw",
+                        Integer.toHexString(typeCode), fixedLen, remaining);
+                blocks.add(new InfoBlock.Raw(typeCode, InfoBlockType.RAW, tail));
+                break;
             }
-            InfoBlock block = parser.parse(body);
+
+            InfoBlock block;
+            try {
+                block = parser.parse(body);
+            } catch (DecodeException | java.nio.BufferUnderflowException | IndexOutOfBoundsException e) {
+                if (!lenientBlockFailure) {
+                    if (e instanceof DecodeException de) throw de;
+                    throw new DecodeException(
+                            "parser " + parser.getClass().getSimpleName() + " failed: " + e.getMessage(), e);
+                }
+                // 回滚到 parser.parse 入口，按块类型分支处理。
+                body.position(posBefore);
+                if (fixedLen >= 0) {
+                    // 固定长度块：按 fixedLen 截取 → 兜 Raw → continue 循环
+                    byte[] corrupt = new byte[fixedLen];
+                    body.get(corrupt);
+                    log.warn("[gb32960] block parse failed typeCode=0x{} parser={} fixedLen={} — isolated as Raw, continuing",
+                            Integer.toHexString(typeCode), parser.getClass().getSimpleName(), fixedLen, e);
+                    blocks.add(new InfoBlock.Raw(typeCode, InfoBlockType.RAW, corrupt));
+                    continue;
+                }
+                // 变长块：无法安全找下一块边界 → 剩余整段兜 Raw + break
+                int remaining = body.remaining();
+                byte[] tail = new byte[remaining];
+                body.get(tail);
+                log.warn("[gb32960] variable-length block parse failed typeCode=0x{} parser={} remaining={} — wrapping remainder as Raw, stopping loop",
+                        Integer.toHexString(typeCode), parser.getClass().getSimpleName(), remaining, e);
+                blocks.add(new InfoBlock.Raw(typeCode, InfoBlockType.RAW, tail));
+                break;
+            }
+
             int consumed = body.position() - posBefore;
             if (fixedLen >= 0 && consumed != fixedLen) {
+                // parser 契约违反（声明 fixedLen=X 但实际读了 Y），保持抛异常以暴露 parser bug，
+                // 不走 lenient 兜底，避免静默误解析长期误判。
                 throw new DecodeException(
                         "parser " + parser.getClass().getSimpleName()
                                 + " consumed " + consumed