[#31438] Non-processing time triggers pass w/accumulation.

[lostluck]

• Effectively makes all aggregation transforms (AKA, GBKs) stateful.
• Adds all non-processing time derived triggers.
• Adds support for Accumulation mode.
• Adds computation of panes for the triggered aggregation results.
• Handles trigger edge case WRT Lifted combines and ElementCount triggers by disabling lifting when one is detected.
• Added some of the Go trigger tests to the engine_test.go file, to maintain coverage.
  • Note, the Go trigger tests are not canonical as the Go SDK has issues regarding panes, largely due to not having any runner that would support testing them. (see [Bug]: PaneInfo not populated in Go SDK #31153)(until prism).

Important notes: Does not support processing time triggers, or triggered side inputs or triggers against merging windows at this PR. Those will be supported at a later PR.

Blocks submission of Processing Time triggers at this time.
TODO doesn't currently do the analysis for blocking Triggered Side Inputs, and triggers for merging windows.

Increases the number of Java Validates Runner tests that pass from 325 to 336.

Part of #31438.

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R: @kennknowles @damccorm

As much as I'd love for Jack to look at this as well, he's doing the release and is busy enough.

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