[processor/tailsampling] Replace invert sampled with drop policy

[portertech]

Description

This pull-request replaces the use of InvertSampled and InvertNotSampled decisions with a new policy type to explicitly drop traces regardless of other policy decisions. The new drop policy type behaves much like an and, however, it returns a Dropped decision when all of its policies return Sampled. A Dropped decision takes precedence over all others. Other policy types will either return Sampled or NotSampled. The string, numeric, and boolean filter policies still support invert_match, which continues to flip the decision for the individual policy. Let invert_match be what it should be.

This is a breaking change, as existing top-level (not within an and or composite) string, numeric, and boolean filter policies used to impact the final decision with its invert_match. They will need to be replaced with a drop, effectively wrapping them.

Using an example invert_match policy from the readme:

{
    name: drop-it-like-its-hot,
    type: drop,
    drop: {
        drop_sub_policy: 
        [
            {
                name: team_a-do-not-sample,
                type: boolean_attribute,
                boolean_attribute: { key: app.do_not_sample, value: true, invert_match: true },
            }
        ]
    }
}

This pull-request also optimizes decision policy evaluation. It will make an earlier decision when drop policy is not used, making a decision on the first Sampled. This reduces tick/decision latency, leading to improved stability and performance.

Related Issues

• [processor/tailsampling] Allow invert matches in composite policy to continue processing #36673
• [processor/tailsampling] invert_match not given precedence when inside and policy #33656
• Tail-based sampling with policies evaluated with first match mechanism #36795
• [processor/tailsampling] numeric attribute invert match evaluation not prioritized #34296
• [processor/tailsampling] invert_match precedence  #34085
• Unexpected behavior of And policy #29637
• Tail-sampling evaluation completing but not filtering out any traces for Grafana Tempo Distributed  #27049
• Probably more 😅