fix(analyzer): name A5/5A frames; revert S3 checksum validation

Add 0x5A (BULK_WAVEFORM_STREAM) and 0xA5 (BULK_WAVEFORM_RESPONSE) to
SUB_TABLE so they display with real names instead of UNKNOWN_5A/A5.

Revert S3 checksum validation to checksum_valid=None (the original
intentional behavior). Large S3 frames (A5 bulk waveform, E5 compliance
config) embed inner DLE+ETX sub-frame delimiters; the trailing 0x03 of
the last inner delimiter can land where the parser expects the SUM8
checksum byte, causing false BAD CHK on every valid A5 frame.
protocol.py _validate_frame documents and ignores exactly this issue.

https://claude.ai/code/session_014NczSHUz9uTzCAf4cVASTJ

parsers/s3_analyzer.py

@@ -53,7 +53,9 @@ SUB_TABLE: dict[int, tuple[str, str, str]] = {
     0x82: ("TRIGGER_CONFIG_WRITE",      "BW→S3", "0x1C bytes; trigger config block; mirrors SUB 1C"),
     0x83: ("TRIGGER_WRITE_CONFIRM",     "BW→S3", "Short frame; commit step after 0x82"),
     # S3→BW responses
+    0x5A: ("BULK_WAVEFORM_STREAM",       "BW→S3", "Bulk waveform chunk request; response is A5 stream"),
     0xA4: ("POLL_RESPONSE",             "S3→BW", "Response to SUB 5B poll"),
+    0xA5: ("BULK_WAVEFORM_RESPONSE",    "S3→BW", "Response to SUB 5A; waveform chunks + metadata"),
     0xFE: ("FULL_CONFIG_RESPONSE",      "S3→BW", "Response to SUB 01"),
     0xF9: ("CHANNEL_CONFIG_RESPONSE",   "S3→BW", "Response to SUB 06"),
     0xF7: ("EVENT_INDEX_RESPONSE",      "S3→BW", "Response to SUB 08; contains backlight/power-save"),