feat(server): implement full REST API with JWT auth and real-time WebSocket

- Add HTTP handlers for issues, comments, agents, workspaces, inbox, members, and activity
- Implement JWT authentication middleware with Bearer token validation
- Add sqlc queries for all entities (CRUD operations)
- Extract router into reusable NewRouter() for testability
- Expand SDK with full API client methods (CRUD for all resources)
- Add updateWorkspace to SDK, add Member type to shared types

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

server/pkg/db/queries/workspace.sql

@@ -0,0 +1,30 @@
+-- name: ListWorkspaces :many
+SELECT w.* FROM workspace w
+JOIN member m ON m.workspace_id = w.id
+WHERE m.user_id = $1
+ORDER BY w.created_at ASC;
+
+-- name: GetWorkspace :one
+SELECT * FROM workspace
+WHERE id = $1;
+
+-- name: GetWorkspaceBySlug :one
+SELECT * FROM workspace
+WHERE slug = $1;
+
+-- name: CreateWorkspace :one
+INSERT INTO workspace (name, slug, description)
+VALUES ($1, $2, $3)
+RETURNING *;
+
+-- name: UpdateWorkspace :one
+UPDATE workspace SET
+    name = COALESCE(sqlc.narg('name'), name),
+    description = COALESCE(sqlc.narg('description'), description),
+    settings = COALESCE(sqlc.narg('settings'), settings),
+    updated_at = now()
+WHERE id = $1
+RETURNING *;
+
+-- name: DeleteWorkspace :exec
+DELETE FROM workspace WHERE id = $1;