refactor(registry): move MCP servers from code to JSON manifests (#1144)

* refactor(registry): move MCP server entries from code to JSON manifests

Move 8 hardcoded MCP server RegistryEntry structs from
builtin_entries() into data-driven JSON files under
registry/mcp-servers/, matching the existing pattern used by
tools and channels. Exclude the GitHub MCP entry which conflicts
with the WASM GitHub tool's OAuth flow.

Extend ManifestKind with McpServer, make version/source optional
on ExtensionManifest (MCP servers don't need them), and add
url/auth fields for MCP-specific config. Update build.rs,
embedded catalog, catalog loader, installer, and CLI display
to handle the new kind and optional fields.

Co-Authored-By: Claude Opus 4.6 (1M context) <[email protected]>

* fix(registry): address PR review — add missing slack-mcp, remove .expect(), fix fmt

- Add missing slack-mcp.json (was dropped during migration)
- Remove production .expect() in get_strict(), replace with .ok_or_else()
- Clean up unwrap_or_default() in key_for() to use .next() directly
- Log warning for MCP manifests missing url field instead of silent empty
- Run cargo fmt to fix formatting diffs

Co-Authored-By: Claude Opus 4.6 (1M context) <[email protected]>

* ci: re-trigger CI with correct base branch (staging)

Co-Authored-By: Claude Opus 4.6 (1M context) <[email protected]>

* fix(ci): improve no-panics check to properly exclude test modules

The grep-based filter only excluded lines literally containing
#[cfg(test)], #[test], or 'mod tests' — not lines *inside* test
modules. Use awk to track hunk context from diff @@ headers and
skip all added lines within test module hunks.

[skip-regression-check]

Co-Authored-By: Claude Opus 4.6 (1M context) <[email protected]>

* refactor(registry): remove slack-mcp MCP entry (conflicts with WASM slack tool)

Remove slack-mcp.json alongside the already-excluded github MCP
entry — both conflict with existing WASM tools of the same name.

Co-Authored-By: Claude Opus 4.6 (1M context) <[email protected]>

* fix(registry): address re-review — skip invalid MCP entries, fix install order

- to_registry_entry() now returns Option<RegistryEntry>; MCP manifests
  missing a url field are skipped with a warning instead of creating
  broken entries with empty URLs
- Move McpServer early-return before require_source() in install paths
  so the error message is clear ("cannot install MCP servers") rather
  than the misleading "missing source spec"
- Add test for MCP manifest with missing URL returning None

Co-Authored-By: Claude Opus 4.6 (1M context) <[email protected]>

---------

Co-authored-by: Claude Opus 4.6 (1M context) <[email protected]>

build.rs

@@ -132,7 +132,7 @@ fn embed_registry_catalog(root: &Path) {
         // No registry dir: write empty catalog
         fs::write(
             &out_path,
-            r#"{"tools":[],"channels":[],"bundles":{"bundles":{}}}"#,
+            r#"{"tools":[],"channels":[],"mcp_servers":[],"bundles":{"bundles":{}}}"#,
         )
         .unwrap();
         return;
@@ -140,6 +140,7 @@ fn embed_registry_catalog(root: &Path) {
 
     let mut tools = Vec::new();
     let mut channels = Vec::new();
+    let mut mcp_servers = Vec::new();
 
     // Collect tool manifests
     let tools_dir = registry_dir.join("tools");
@@ -153,6 +154,12 @@ fn embed_registry_catalog(root: &Path) {
         collect_json_files(&channels_dir, &mut channels);
     }
 
+    // Collect MCP server manifests
+    let mcp_servers_dir = registry_dir.join("mcp-servers");
+    if mcp_servers_dir.is_dir() {
+        collect_json_files(&mcp_servers_dir, &mut mcp_servers);
+    }
+
     // Read bundles
     let bundles_path = registry_dir.join("_bundles.json");
     let bundles_raw = if bundles_path.is_file() {
@@ -163,9 +170,10 @@ fn embed_registry_catalog(root: &Path) {
 
     // Build the combined JSON
     let catalog = format!(
-        r#"{{"tools":[{}],"channels":[{}],"bundles":{}}}"#,
+        r#"{{"tools":[{}],"channels":[{}],"mcp_servers":[{}],"bundles":{}}}"#,
         tools.join(","),
         channels.join(","),
+        mcp_servers.join(","),
         bundles_raw,
     );