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.

python/ktx-daemon/src/ktx_daemon/app.py

@@ -1,4 +1,4 @@
-"""FastAPI app factory for the KTX daemon semantic compute server."""
+"""FastAPI app factory for the ktx daemon semantic compute server."""
 
 from __future__ import annotations
 
@@ -142,8 +142,8 @@ def create_app(
             )
 
     app = FastAPI(
-        title="KTX Daemon",
-        description="Stateless portable compute server for KTX.",
+        title="ktx Daemon",
+        description="Stateless portable compute server for ktx.",
         version=VERSION,
         lifespan=lifespan,
     )