Code cleanup

[sameelarif]

why

lib/index.ts was getting cluttered

what changed

I moved all stagehand classes into the lib/stagehand folder and also created a singular export for all types

test plan

Run existing evals to ensure no breaking changes and/or performance degradations occured.

[changeset-bot[bot]]

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Latest commit: 1ef921ff336d547a34bc7aecd5e43d28feb7ee53

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[kamath]

closing since this is unnecessary; idt the current codebase is particularly hard to read