Add multi-repository support for chains

Chains can now have multiple repositories attached, with one marked as
primary. Repositories are used by contracts created from chain definitions.

Backend changes:
- Add chain_repositories table migration
- Add ChainRepository model with CRUD operations
- Add API endpoints for listing, adding, deleting repositories
- Add endpoint to set a repository as primary
- Update Chain and ChainEditorData models to use repositories
- Update chain parser to support repositories in YAML format
- Remove deprecated repository_url/local_path from Chain

Frontend changes:
- Add ChainRepository interface and API functions
- Add repository section to ChainEditor showing attached repos
- Add modal for adding new repositories (remote or local)
- Support setting primary repository and removing repositories

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

1 files changed, 13 insertions, 0 deletions

diff --git a/makima/src/server/mod.rs b/makima/src/server/mod.rs
index 5dde099..f6d2eda 100644
--- a/makima/src/server/mod.rs
+++ b/makima/src/server/mod.rs
@@ -245,6 +245,19 @@ pub fn make_router(state: SharedState) -> Router {
         // Chain control
         .route("/chains/{id}/start", post(chains::start_chain))
         .route("/chains/{id}/stop", post(chains::stop_chain))
+        // Chain repositories
+        .route(
+            "/chains/{id}/repositories",
+            get(chains::list_chain_repositories).post(chains::add_chain_repository),
+        )
+        .route(
+            "/chains/{chain_id}/repositories/{repository_id}",
+            axum::routing::delete(chains::delete_chain_repository),
+        )
+        .route(
+            "/chains/{chain_id}/repositories/{repository_id}/primary",
+            put(chains::set_chain_repository_primary),
+        )
         // Contract type templates (built-in only)
         .route("/contract-types", get(templates::list_contract_types))
         // Settings endpoints