fix(ebpf): correct logical operator bugs in protocol_inference.h

[kalakotima]

Summary

This PR fixes multiple critical logical operator bugs in
agent/src/ebpf/kernel/include/protocol_inference.h that affect
protocol identification for HTTP/1.x, PostgreSQL, ISO8583, Redis,
and NATS protocols.

Root Cause

Several functions contained two categories of operator errors:

These errors cause silent logic failures — the eBPF program loads
and runs but produces "wrong protocol inference results" at runtime.

The following bugs were identified and fixed:

1. __protocol_port_check(): comma operator ',' used instead of '||'
   in the L7_PROTO_INFER_PROG_1 branch, causing the first
   is_set_bitmap() result to be silently discarded, leading to
   incorrect port-based protocol filtering.

2. is_http_request(): array close bracket ']' used instead of '||'
   combined with proper array indexing 'data[N]' across all HTTP
   method checks (DELETE, GET, HEAD, OPTIONS, PATCH, POST, PUT),
   breaking all multi-character method validation.

3. infer_pgsql_startup_message(): array close bracket ']' used
   instead of '||' in the "user" string validation check for
   buf[8..11], breaking PostgreSQL startup message detection.

4. infer_iso8583_message(): array close bracket ']' used instead
   of '||' in CUPS header flag checks and buffer content validation,
   breaking ISO8583 protocol identification entirely.

5. infer_redis_message(): array close bracket ']' used instead of
   '||' in the error prefix validation (buf[2] check), causing
   valid Redis error responses to be incorrectly dropped.

6. infer_nats_message(): array close bracket ']' used instead of
   '||' in the CRLF terminator check, causing all NATS protocol
   messages to be rejected during initial socket inference.

These bugs collectively affect HTTP/1.x, PostgreSQL, ISO8583, Redis,
and NATS protocol inference, causing silent misidentification or
complete failure to detect these protocols in production environments.

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✅ kalakotima
❌ kalakotima@gmail.com

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