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/IntelCore2DuoT6600/catproc.txt

@@ -0,0 +1,26 @@
+processor	: 0
+vendor_id	: GenuineIntel
+cpu family	: 6
+model		: 23
+model name	: Intel(R) Core(TM)2 Duo CPU     T6600  @ 2.20GHz
+stepping	: 10
+microcode	: 0xa0b
+cpu MHz		: 2200.000
+cache size	: 2048 KB
+physical id	: 0
+siblings	: 2
+core id		: 0
+cpu cores	: 2
+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 dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx lm constant_tsc arch_perfmon pebs bts rep_good nopl cpuid aperfmperf pni dtes64 monitor ds_cpl est tm2 ssse3 cx16 xtpr pdcm sse4_1 xsave lahf_lm pti retpoline dtherm
+bugs		: cpu_meltdown spectre_v1 spectre_v2
+bogomips	: 4388.94
+clflush size	: 64
+cache_alignment	: 64
+address sizes	: 36 bits physical, 48 bits virtual
+power management:

benchmark-data/data/hardware/IntelCore2DuoT6600/lscpu.txt

@@ -0,0 +1,14 @@
+Architecture:          i686
+CPU op-mode(s):        32-bit, 64-bit
+CPU(s):                2
+Hilo(s) por n?cleo:    1
+N?cleo(s) por z?calo:  2
+Z?calo(s) de CPU:      1
+ID del vendedor:       GenuineIntel
+Familia de CPU:        6
+Modelo:                23
+Stepping:              10
+CPU MHz:               1200.000
+cach? L1d:             32K
+cach? L1i:             32K
+cach? L2:              2048K