[FEATURE][v13+] Actor/Item Sheet rework

[BoltsJ]

V13 officially deprecates Application v1 with v16 being the scheduled removal of application v1. Aside from the appv2 switch over, the sheets are carrying a lot of technical debt and custom redundant solutions. While a conversion would be possible, it would be a lot better to make a clean break and rewrite the sheets underlying code to take advantage tools that foundry provides.

• Split the headers, tab bars and sheet bodies into separate hbs templates. Foundry provides a stock tab bar template that is easy to restyle to our needs.
• Remove redundant and unused/under-used helpers. We have a lot of handlebars helpers that replicate helpers already provided by foundry.
• Utilize formInput and fromGroup helpers to reduce the amount of template code we need to write
• Utilize modules and nesting in style files to improve organization. Ensure that all styles are namespaced properly to prevent clobbering base foundry styles. Potentially use layers aside from the automatic system layer.
• Improve effects tab to allow for creation and deletion of custom effects
• Use built in foundry drag/drop functionality instead of hand-rolled implementation