refactor: enforce ktx naming and AGENTS.md compliance sweep (#289)

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.

scripts/build-python-runtime-wheel.test.mjs

@@ -70,7 +70,7 @@ describe('runtimeWheelPyproject', () => {
 });
 
 describe('createRuntimeWheelBuildTree', () => {
-  it('copies KTX-owned Python packages into the build tree', async () => {
+  it('copies ktx-owned Python packages into the build tree', async () => {
     const root = await mkdtemp(join(tmpdir(), 'ktx-runtime-wheel-test-'));
     try {
       await writeRuntimeSourceFixture(root);
@@ -90,7 +90,7 @@ describe('createRuntimeWheelBuildTree', () => {
       assert.match(pyproject, /name = "kaelio-ktx"/);
       assert.match(pyproject, /local-embeddings = \[/);
       const readme = await readFile(join(layout.buildRoot, 'README.md'), 'utf8');
-      assert.match(readme, /Bundled Python runtime wheel for KTX/);
+      assert.match(readme, /Bundled Python runtime wheel for ktx/);
     } finally {
       await rm(root, { recursive: true, force: true });
     }