Defer statistics update until first access to improve performance

[dwelch-r7]

Description

Defer stats calculation until we need it, this results in running msfconsole with the -q flag spinning up a 0.3-0.5s faster, I haven't removed the stats from the banner but I think we should consider it since it's really not that useful and it's adding time to the boot up process.

Verification Steps

1. • Start msfconsole normally (without -q) — banner should display correct module counts as before
2. • Start msfconsole -q -x 'exit' — should boot and exit without error
3. • In msfconsole, run banner command — module counts should display correctly
4. • Run bundle exec rspec spec/lib/msf/base/simple/statistics_spec.rb — all 11 examples pass

Test Evidence

with -q

hyperfine  --warmup 3 "bundle exec ruby ./msfconsole -q -x 'exit'"                                                                                                     
Benchmark 1: bundle exec ruby ./msfconsole -q -x 'exit'
  Time (mean ± σ):      3.732 s ±  0.034 s    [User: 2.561 s, System: 1.242 s]
  Range (min … max):    3.679 s …  3.777 s    10 runs

without -q

hyperfine  --warmup 3 "bundle exec ruby ./msfconsole -x 'exit'"                                                                                                        
Benchmark 1: bundle exec ruby ./msfconsole -x 'exit'
  Time (mean ± σ):      4.263 s ±  0.094 s    [User: 3.008 s, System: 1.319 s]
  Range (min … max):    4.178 s …  4.485 s    10 runs

Environment

Field	Details
Operating System	macOS (26.5.2)
Target Software/Hardware	Metasploit Framework (Ruby 3.3.8)

AI Usage Disclosure

Kiro

Pre-Submission Checklist

• No sensitive information (IP addresses, credentials, API keys, hashes) in code or documentation
• Tested on the target environment specified in the Environment section above
• Included RSpec tests for library changes
• Read the CONTRIBUTING.md and module acceptance guidelines