feat: improve build workflows and connection handling

[Day-Anger]

CI/CD:

Add Cargo cache for git dependencies in bridge.yml
Add nick-fields/retry action in bridge.yml
Update actions versions
Fix generator-android.yml, generator-linux.yml, generator-windows-x86.yml

Connection & Networking:

Fix connection delay: replace broad !key.is_empty() condition with precise timeout check, preserving TCP encryption and UDP logic
Fix timeout for file transfer to rdgen server and API server
Add server port support with dynamic port calculation (RENDEZVOUS_PORT, RELAY_PORT, WS_RENDEZVOUS_PORT, WS_RELAY_PORT)

Build Customization:

Change company name step: rewrite from bash/sed to Python for proper UTF-8 and special characters support («, ', `, ~, CJK, etc.)
Change appname step: rewrite from bash/sed to Python for proper UTF-8 and special characters support; add empty filename guard
Add UTF-8 stdout/stderr wrapper in decrypt-secrets action to handle special characters in secret values