chore(app): general tidy for release

[Jacobbrewer1]

Describe your changes

This pull request includes several changes to the app.go and options.go files to improve configuration management, error handling, and code readability. The most important changes include the introduction of new configuration options, enhanced error handling, and the removal of redundant code.

Improvements to configuration management:

• app.go: Added new constants httpReadHeaderTimeout and shutdownTimeout for better configuration management.
• options.go: Introduced WithViperConfig and WithConfigWatchers functions to set up and watch Viper configuration.

Enhanced error handling:

• app.go: Added error logging and panics for unregistered components like the logger, vault client, viper instance, database connection, Kubernetes client, etc. [1] [2] [3]
• options.go: Improved error messages and checks in functions like WithLeaderElection, WithRedisPool, and WithNatsClient. [1] [2] [3]

Code readability and simplification:

• app.go: Removed redundant Viper setup code from the NewApp function.
• app.go: Changed log level from Info to Debug for leader election status.
• options.go: Replaced hardcoded leader election durations with constants.

[Copilot]

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

Comments suppressed due to low confidence (1)

app.go:149

• The viper instance created in NewApp is no longer assigned to the app struct, which could lead to a panic when calling a.Viper(). Consider storing the viper instance (e.g. via WithViperConfig) into the app's vip field to ensure it is available.

return &App{ ... }

[github-actions]

I'm going to lock this pull request because it has been closed for 30 days ⏳. This helps our maintainers find and focus on the active issues.
If you have found a problem that seems related to this change, please open a new issue and complete the issue template so we can capture all the details necessary to investigate further.