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/IntelCorei5760/catproc.txt

@@ -0,0 +1,26 @@
+processor	: 0
+vendor_id	: GenuineIntel
+cpu family	: 6
+model		: 30
+model name	: Intel(R) Core(TM) i5 CPU         760  @ 2.80GHz
+stepping	: 5
+microcode	: 0x7
+cpu MHz		: 2209.422
+cache size	: 8192 KB
+physical id	: 0
+siblings	: 4
+core id		: 0
+cpu cores	: 4
+apicid		: 0
+initial apicid	: 0
+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 syscall nx rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc cpuid aperfmperf pni dtes64 monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr pdcm sse4_1 sse4_2 popcnt lahf_lm pti tpr_shadow vnmi flexpriority ept vpid dtherm ida
+bugs		: cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass l1tf
+bogomips	: 5619.27
+clflush size	: 64
+cache_alignment	: 64
+address sizes	: 36 bits physical, 48 bits virtual
+power management:

benchmark-data/data/hardware/IntelCorei5760/lscpu.txt

@@ -0,0 +1,21 @@
+Architecture:          x86_64
+Tryb(y) pracy CPU:     32-bit, 64-bit
+Byte Order:            Little Endian
+CPU(s):                4
+On-line CPU(s) list:   0-3
+Wątków na rdzeń:    1
+Rdzeni na gniazdo:     4
+Socket(s):             1
+Węzłów NUMA:        1
+ID producenta:         GenuineIntel
+Rodzina CPU:           6
+Model:                 30
+Wersja:                5
+CPU MHz:               2879.880
+BogoMIPS:              5759.76
+Wirtualizacja:         VT-x
+Cache L1d:             32K
+Cache L1i:             32K
+Cache L2:              256K
+Cache L3:              8192K
+NUMA node0 CPU(s):     0-3