deps: upgrade rmcp/rmcp-macros 0.6 -> 1.7 with API migration

rmcp 1.x made several MCP model result structs #[non_exhaustive] and
added new fields (e.g. `_meta`), which broke the existing struct-literal
construction in the MCP server. Migrate all construction sites to the
crate's constructors/builders while preserving behavior exactly:

- CallToolResult (now #[non_exhaustive]): replace struct literals with
  CallToolResult::success(content) + assign .structured_content; keeps
  same content, is_error=Some(false), structured_content, meta=None.
- Tool (now #[non_exhaustive], +execution/+meta fields): use
  Tool::new(name, description, input_schema).with_title(title).
- ListToolsResult (+_meta field): use ListToolsResult::with_all_items(tools)
  (next_cursor=None, meta=None as before).
- ServerCapabilities (#[non_exhaustive]): use the builder,
  .enable_tools_with(ToolsCapability { list_changed: Some(false) }).
- Implementation / InitializeResult (#[non_exhaustive]): build via
  Implementation::new(..).with_title(..).with_website_url(..) and
  InitializeResult::new(caps).with_protocol_version(..).with_server_info(..)
  .with_instructions(..).
- Switch deprecated type aliases CallToolRequestParam/PaginatedRequestParam
  to CallToolRequestParams/PaginatedRequestParams.

Pinned to rmcp 1.7.0 in Cargo.lock. cargo check/clippy/fmt clean;
all ck-search tests pass (83 passed, 2 ignored).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: runonthespot

Cargo.lock

@@ -36,8 +36,8 @@ serde_json = { workspace = true }
 tokio = { workspace = true }
 tracing = { workspace = true }
 tracing-subscriber = { workspace = true }
-rmcp = { version = "0.6", features = ["transport-io"] }
-rmcp-macros = "0.6"
+rmcp = { version = "1.7", features = ["transport-io"] }
+rmcp-macros = "1.7"
 tokio-util = { version = "0.7", features = ["rt", "full"] }
 chrono = { version = "0.4", features = ["serde"] }
 thiserror = { workspace = true }