feat: 대역폭 추정 및 DAU 표시 기능 추가

- 동시접속자 기반 월간 대역폭 자동 추정
- DAU(일일활성사용자) 추정치 표시 (동접 × 10-14)
- 대역폭 기반 Linode/Vultr 자동 선택 로직
- 비용 분석에 대역폭 비용 포함
- 지역 미선택시 서울/도쿄/오사카/싱가포르 기본 표시
- 지역별 서버 분리 표시 (GROUP BY instance + region)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

benchmark-data/data/hardware/IntelCorei5-2320/catproc.txt

@@ -0,0 +1,25 @@
+processor	: 0
+vendor_id	: GenuineIntel
+cpu family	: 6
+model		: 42
+model name	: Intel(R) Core(TM) i5-2320 CPU @ 3.00GHz
+stepping	: 7
+microcode	: 0xffffffff
+cpu MHz		: 3009.321
+cache size	: 6144 KB
+physical id	: 0
+siblings	: 4
+core id		: 0
+cpu cores	: 4
+apicid		: 0
+initial apicid	: 0
+fpu		: yes
+fpu_exception	: yes
+cpuid level	: 13
+wp		: yes
+flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ss ht syscall nx lm constant_tsc rep_good nopl pni ssse3 cx16 sse4_1 sse4_2 popcnt xsave avx hypervisor lahf_lm
+bogomips	: 6018.64
+clflush size	: 64
+cache_alignment	: 64
+address sizes	: 36 bits physical, 48 bits virtual
+power management:

benchmark-data/data/hardware/IntelCorei5-2320/lscpu.txt

@@ -0,0 +1,22 @@
+Architecture:          x86_64
+Operační režim(y) CPU:32-bit, 64-bit
+Byte Order:            Little Endian
+CPU(s):                4
+On-line CPU(s) list:   0-3
+Vláken na jádro:     1
+Jader na patici:       4
+Socket(s):             1
+Uzly NUMA:             1
+ID výrobce:           GenuineIntel
+Rodina CPU:            6
+Model:                 42
+Stepping:              7
+CPU MHz:               3009.321
+BogoMIPS:              6021.19
+Výrobce hypervizoru:  Microsoft
+Druh virtualizace:     full
+L1d cache:             32K
+L1i cache:             32K
+L2 cache:              256K
+L3 cache:              6144K
+NUMA node0 CPU(s):     0-3