[pratikbuilds]

Compose the new chat family from the shared samples into one story, in both scroll policies: a conversation with agent steps, approvals and generated images, a prompt input with its toolbar and attachments, the conversation map and history window, and a panel with a thread tab. A browser spec drives the story to check that sending settles, approvals keep keyboard focus after they fold, and attachments move into the sent message.

Stacked on #14: review only this commit. Part of corbitsdev#94.

Notes for review

• e2e/full-chat.spec.ts drives the built Storybook story (the :61000 server the axe sweep already uses) rather than an e2e/fixtures.tsx route: fixtures can't import stories/, and a fixture copy would test a duplicate of the composition. It depends on the story ids.
• After a keyboard approval decision folds the call, the story moves focus to the run's ActivityTrigger (or the batch's next waiting call); asserted under settle and stick.
• Left out: the failed-send sample (covered in Chat / Message), MessageActionMenu and PromptInputContext.

Verification

• This commit passes bun run typecheck and bun run lint on its own (the stack is checked commit by commit).
• At the top of the stack: bun run check, bun run build, bun run dep-guard, bun run contrast-test and bun run test:e2e (Playwright specs and the Storybook axe sweep in light and dark) pass.

Closes corbitsdev#109

[pratikbuilds]

Moved upstream: corbitsdev#127