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.

examples/README.md

@@ -17,7 +17,7 @@ The copied project initializes its own Git repository on first use.
 
 ## orbit-relationship-verification
 
-`orbit-relationship-verification/` is a checked-in KTX project used by
+`orbit-relationship-verification/` is a checked-in **ktx** project used by
 `pnpm run relationships:verify-orbit`. It points the `orbit` SQLite connection
 at the Orbit-style no-declared-constraint relationship fixture and verifies that
 relationship enrichment writes nine accepted joins without requiring a local
@@ -27,7 +27,7 @@ warehouse credential.
 
 `postgres-historic/` is a manual Docker-backed smoke for Postgres
 query-history ingest via `pg_stat_statements`. It verifies setup, staged
-query-history artifacts, KTX daemon batch SQL analysis, bounded pattern
+query-history artifacts, **ktx** daemon batch SQL analysis, bounded pattern
 WorkUnit shards, and no-WorkUnit idempotency for unchanged bucketed table
 inputs and pattern shards.