Align the tree with AGENTS.md/CLAUDE.md conventions:
- Rewrite user-facing strings, docs, and tests to lowercase `ktx`
(no bare uppercase `KTX` tokens remain outside literal identifiers).
- Drop the legacy `historicSql` migration path and its now-unused
helpers, per the no-backward-compat rule.
- Remove `as unknown as` / `any` casts: narrow `BaseTool` generics to
`z.ZodObject`, add a typed `createLookerClient`, and delete the dead
`getParametersSchema`/`toAnthropicFormat` pre-AI-SDK helpers.
- Use `InvalidArgumentError` for Commander parse failures.
- Finish the adapter→connector prose conversion in the `ktx.yaml` docs
while keeping the literal `adapters` config key.
The staleness check compared source mtimes against packages/cli/dist/bin.js,
but tsc only rewrites outputs whose source actually changed. Editing any
non-bin source (e.g. setup.ts) left bin.js untouched, so its mtime stayed
older than the sources forever and every `pnpm run ktx` invocation
rebuilt the whole workspace. Write a dedicated .ktx-build-stamp after a
successful build and check sources against that instead.
