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/IntelAtomE3815/catproc.txt

@@ -0,0 +1,28 @@
+processor	: 0
+vendor_id	: GenuineIntel
+cpu family	: 6
+model		: 55
+model name	: Intel(R) Atom(TM) CPU  E3815  @ 1.46GHz
+stepping	: 3
+microcode	: 0x321
+cpu MHz		: 1100.000
+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	: 11
+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 nx rdtscp lm constant_tsc arch_perfmon pebs bts xtopology nonstop_tsc aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm sse4_1 sse4_2 movbe popcnt tsc_deadline_timer aes rdrand lahf_lm 3dnowprefetch arat epb dtherm tpr_shadow vnmi flexpriority ept vpid tsc_adjust smep erms
+bogomips	: 2933.11
+clflush size	: 64
+cache_alignment	: 64
+address sizes	: 36 bits physical, 48 bits virtual
+power management:

benchmark-data/data/hardware/IntelAtomE3815/lscpu.txt

@@ -0,0 +1,18 @@
+Architecture:          i686
+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
+Vendor ID:             GenuineIntel
+CPU family:            6
+Model:                 55
+Stepping:              3
+CPU MHz:               1100.000
+BogoMIPS:              2933.11
+Virtualization:        VT-x
+L1d cache:             24K
+L1i cache:             32K
+L2 cache:              512K