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/IntelPentium42.66GHz/catproc.txt

@@ -0,0 +1,28 @@
+processor	: 0
+vendor_id	: GenuineIntel
+cpu family	: 15
+model		: 2
+model name	: Intel(R) Pentium(R) 4 CPU 2.66GHz
+stepping	: 7
+microcode	: 0x33
+cpu MHz		: 2665.891
+cache size	: 512 KB
+physical id	: 0
+siblings	: 1
+core id		: 0
+cpu cores	: 1
+apicid		: 0
+initial apicid	: 0
+fdiv_bug	: no
+f00f_bug	: no
+coma_bug	: no
+fpu		: yes
+fpu_exception	: yes
+cpuid level	: 2
+wp		: yes
+flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe pebs bts eagerfpu cid xtpr
+bogomips	: 5331.78
+clflush size	: 64
+cache_alignment	: 128
+address sizes	: 36 bits physical, 32 bits virtual
+power management:

benchmark-data/data/hardware/IntelPentium42.66GHz/lscpu.txt

@@ -0,0 +1,15 @@
+Architecture:          i686
+CPU op-mode(s):        32-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
+Vendor ID:             GenuineIntel
+CPU family:            15
+Model:                 2
+Model name:            Intel(R) Pentium(R) 4 CPU 2.66GHz
+Stepping:              7
+CPU MHz:               2665.891
+BogoMIPS:              5331.78