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/Loongson-3AR3/catproc.txt

@@ -0,0 +1,20 @@
+system type		: generic-loongson-machine
+machine			: Unknown
+processor		: 0
+cpu model		: Loongson-3 V0.9  FPU V0.1
+model name		: Loongson-3A R3 (Loongson-3A3000) @ 1400MHz
+CPU MHz			: 1400.04
+BogoMIPS		: 2785.88
+wait instruction	: yes
+microsecond timers	: yes
+tlb_entries		: 1088
+extra interrupt vector	: no
+hardware watchpoint	: yes, count: 0, address/irw mask: []
+isa			: mips1 mips2 mips3 mips4 mips5 mips32r1 mips32r2 mips64r1 mips64r2
+ASEs implemented	: dsp dsp2 vz
+shadow register sets	: 1
+kscratch registers	: 6
+package			: 0
+core			: 0
+VCED exceptions		: not available
+VCEI exceptions		: not available

benchmark-data/data/hardware/Loongson-3AR3/lscpu.txt

@@ -0,0 +1,16 @@
+Architecture:        mips64
+Byte Order:          Little Endian
+CPU(s):              4
+On-line CPU(s) list: 0-3
+Thread(s) per core:  1
+Core(s) per socket:  4
+Socket(s):           1
+NUMA node(s):        1
+Model name:          Loongson-3A R3 (Loongson-3A3000) @ 1400MHz
+CPU max MHz:         1400.0400
+CPU min MHz:         350.0100
+BogoMIPS:            2785.88
+L1d cache:           64K
+L1i cache:           64K
+L2 cache:            2048K
+NUMA node0 CPU(s):   0-3