Chore: Move active context files

What does this MR do and why?

Move active context files from ai/context/ to ai/active_context/ per &17524 (comment 2519321629)

Before

.
├── context
│   ├── chunkers
│   ├── collections
│   ├── dependencies
│   ├── queues
│   └── references

After

.
├── active_context
│   ├── chunkers
│   ├── collections
│   ├── queues
│   └── references
├── context
│   └── dependencies

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