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.

packages/cli/src/connectors/clickhouse/connector.ts

@@ -645,7 +645,7 @@ export class KtxClickHouseScanConnector implements KtxScanConnector {
 
   private assertConnection(connectionId: string): void {
     if (connectionId !== this.connectionId) {
-      throw new Error(`KTX ClickHouse connector ${this.id} cannot serve connection ${connectionId}`);
+      throw new Error(`ktx ClickHouse connector ${this.id} cannot serve connection ${connectionId}`);
     }
   }
 }

packages/cli/src/connectors/mysql/connector.ts

@@ -794,7 +794,7 @@ export class KtxMysqlScanConnector implements KtxScanConnector {
 
   private assertConnection(connectionId: string): void {
     if (connectionId !== this.connectionId) {
-      throw new Error(`KTX MySQL connector ${this.id} cannot serve connection ${connectionId}`);
+      throw new Error(`ktx MySQL connector ${this.id} cannot serve connection ${connectionId}`);
     }
   }
 }

packages/cli/src/connectors/snowflake/connector.ts

@@ -107,7 +107,7 @@ export interface KtxSnowflakeScanConnectorOptions {
   connectionId: string;
   connection: KtxSnowflakeConnectionConfig | undefined;
   /**
-   * KTX project directory. When provided, snowflake-sdk's logger is redirected to
+   * ktx project directory. When provided, snowflake-sdk's logger is redirected to
    * `<projectDir>/.ktx/logs/snowflake.log` so its JSON output does not bleed into
    * the CLI's TTY. Tests that use a fake driverFactory can leave this undefined.
    */

packages/cli/src/connectors/sqlite/connector.ts

@@ -355,7 +355,7 @@ export class KtxSqliteScanConnector implements KtxScanConnector {
 
   private assertConnection(connectionId: string): void {
     if (connectionId !== this.connectionId) {
-      throw new Error(`KTX SQLite connector ${this.id} cannot serve connection ${connectionId}`);
+      throw new Error(`ktx SQLite connector ${this.id} cannot serve connection ${connectionId}`);
     }
   }
 }

packages/cli/src/connectors/sqlserver/connector.ts

@@ -833,7 +833,7 @@ export class KtxSqlServerScanConnector implements KtxScanConnector {
 
   private assertConnection(connectionId: string): void {
     if (connectionId !== this.connectionId) {
-      throw new Error(`KTX SQL Server connector ${this.id} cannot serve connection ${connectionId}`);
+      throw new Error(`ktx SQL Server connector ${this.id} cannot serve connection ${connectionId}`);
     }
   }
 }