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/AMDAthlon643500/catproc.txt

@@ -0,0 +1,26 @@
+processor	: 0
+vendor_id	: AuthenticAMD
+cpu family	: 15
+model		: 79
+model name	: AMD Athlon(tm) 64 Processor 3500+
+stepping	: 2
+microcode	: 0x62
+cpu MHz		: 2210.142
+cache size	: 512 KB
+physical id	: 0
+siblings	: 1
+core id		: 0
+cpu cores	: 1
+apicid		: 0
+initial apicid	: 0
+fpu		: yes
+fpu_exception	: yes
+cpuid level	: 1
+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 syscall nx mmxext fxsr_opt rdtscp lm 3dnowext 3dnow rep_good nopl extd_apicid pni cx16 lahf_lm svm extapic cr8_legacy
+bogomips	: 4420.28
+TLB size	: 1024 4K pages
+clflush size	: 64
+cache_alignment	: 64
+address sizes	: 40 bits physical, 48 bits virtual
+power management: ts fid vid ttp tm stc

benchmark-data/data/hardware/AMDAthlon643500/lscpu.txt

@@ -0,0 +1,20 @@
+Architecture:          x86_64
+CPU op-mode(s):        32-bit, 64-bit
+Byte Order:            Little Endian
+CPU(s):                1
+On-line CPU(s) list:   0
+Thread(s) per core:    1
+Core(s) per socket:    1
+Socket(s):             1
+NUMA node(s):          1
+Vendor ID:             AuthenticAMD
+CPU family:            15
+Model:                 79
+Stepping:              2
+CPU MHz:               2210.142
+BogoMIPS:              4420.28
+Virtualization:        AMD-V
+L1d cache:             64K
+L1i cache:             64K
+L2 cache:              512K
+NUMA node0 CPU(s):     0