developer UX (local emulator, contract tests, bootstrap tooling)

## Summary
Improve developer workflow with local emulation and one-command bootstrap.

## Motivation
Fast local iteration reduces production debugging and integration mistakes.

## Proposal
- `litefunctions dev` local runner that emulates invoke path.
- Generated contract tests for function handlers.
- One-command project bootstrap templates.
- Runtime parity checks between local and cluster execution.

## Acceptance criteria
- Local dev command can run sync/async invoke loops.
- Template project includes tests and CI wiring.
- Docs cover quickstart from zero to deployed function.

Start by mapping the existing CLI entry points and runtime execution path before separating the proposal into local emulation, generated contract tests, bootstrap templates, and parity checks. Done means sync and async invoke loops work locally, templates include tests and CI wiring, and the quickstart documents deployment from an empty project.

Written by the indexing model from the issue text.