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/relationship-orbit-verification.mjs

@@ -197,7 +197,7 @@ function formatBlocked(result) {
 
 export function formatOrbitVerificationMarkdown(result) {
   const lines = [
-    '# KTX Relationship Discovery Orbit Verification',
+    '# ktx Relationship Discovery Orbit Verification',
     '',
     `Date: ${result.date}`,
     '',
@@ -323,7 +323,7 @@ export async function runOrbitVerification(options = {}) {
         projectDir,
         scanCommand,
         scanExitCode: scan.exitCode,
-        blocker: 'KTX scan completed without printing a Run id',
+        blocker: 'ktx scan completed without printing a Run id',
         scanStdout: scan.stdout,
         scanStderr: scan.stderr,
       };
@@ -337,7 +337,7 @@ export async function runOrbitVerification(options = {}) {
           projectDir,
           scanCommand,
           scanExitCode: scan.exitCode,
-          blocker: 'KTX scan completed without printing a report artifact path',
+          blocker: 'ktx scan completed without printing a report artifact path',
           scanStdout: scan.stdout,
           scanStderr: scan.stderr,
         };