fix: scrub sensitive values from logcat + gate logs behind BuildConfig.DEBUG

[jguillaumesio]

Summary

• Redact target number (asterisks) in all log statements
• Redact expected code value, log only its length
• Redact trigger key in logs
• Wrap all Log.d calls in BuildConfig.DEBUG guard so they are stripped from release builds
• Incoming call number redacted in logcat

Why

Sensitive values (intercom number, door code) were being logged in plaintext via Log.d. On a rooted device or via adb logcat, anyone could read them. The app controls physical access to your home — leaking these in logs is a real security issue.

Changes

• IntercomModule.kt: All Log.d calls now wrapped in if (BuildConfig.DEBUG) blocks
• Sensitive values replaced with asterisks or length-only hints
• Log.e calls (error handling) preserved since they do not leak secrets

Test plan

• Build release APK and verify no sensitive values in logcat
• Build debug APK and verify redacted logs still appear
• Verify app functionality is unchanged (no behavioral changes)