feat: generic project UI, branding fix, context/artifact separation

Web:
- Replace GitHub-specific import with generic public Git URL import
- Update project workspace page to use ProjectView shape (name, sources)
- Migrate use-project-workspace hook to importPublicGit action
- Fix status key needsInput → needs-input

Branding:
- Correct Zopo/zopo → Zopu/zopu in docs/PRODUCT.md, docs/DESIGN.md, docs/TECH.md

Artifacts:
- Cut to 8 operational artifacts (removed project/business/design.md)
- Update artifact seeds with generic context scaffolding

packages/backend/convex/projectIssues.ts

@@ -1,6 +1,5 @@
 import { ConvexError, v } from "convex/values";
 
-import type { Id } from "./_generated/dataModel";
 import { mutation, query } from "./_generated/server";
 import { requireProjectMember } from "./authz";