Merge pull request #725 from temitope-007/feature/issue-652-664

feat(docs): Add sequence diagrams and expand open source issues (#652, #664)

Author: ritik4ever

ARCHITECTURE_DIAGRAMS.md

@@ -386,3 +386,48 @@ This comprehensive architecture ensures:
 - ✅ Perfect database isolation
 - ✅ Production safety
 - ✅ Full CI/CD automation
+
+## Freighter Pledge Signing Flow
+
+```mermaid
+sequenceDiagram
+    participant User
+    participant Frontend
+    participant Freighter Wallet
+    participant Soroban RPC
+    participant Smart Contract
+
+    User->>Frontend: Click "Pledge" & Enter Amount
+    Frontend->>Freighter Wallet: Request Signature (XDR)
+    Freighter Wallet-->>User: Prompt for Approval
+    User->>Freighter Wallet: Approve Transaction
+    Freighter Wallet-->>Frontend: Return Signed Transaction
+    Frontend->>Soroban RPC: Submit Transaction
+    Soroban RPC->>Smart Contract: Execute Pledge
+    Smart Contract-->>Soroban RPC: Transaction Success (Events)
+    Soroban RPC-->>Frontend: Return TxHash & Success
+    Frontend-->>User: Display Success Notification
+```
+
+![Pledge Flow Fallback](https://raw.githubusercontent.com/temitope-007/stellar-goal-vault/main/docs/assets/pledge_flow.png)
+
+## Refund Flow
+
+```mermaid
+sequenceDiagram
+    participant Contributor
+    participant Frontend
+    participant Soroban RPC
+    participant Smart Contract
+
+    Note over Contributor, Smart Contract: Campaign Deadline Passed & Funding Failed
+    Contributor->>Frontend: Click "Refund"
+    Frontend->>Soroban RPC: Submit Refund Transaction
+    Soroban RPC->>Smart Contract: Execute Refund Call
+    Smart Contract->>Smart Contract: Verify Failed State & Contributor Amount
+    Smart Contract-->>Soroban RPC: Transfer Asset Back & Return Success
+    Soroban RPC-->>Frontend: Return TxHash
+    Frontend-->>Contributor: Display Refund Success Notification
+```
+
+![Refund Flow Fallback](https://raw.githubusercontent.com/temitope-007/stellar-goal-vault/main/docs/assets/refund_flow.png)

OPEN_SOURCE_ISSUES.md

@@ -1,41 +1,129 @@
 # Open Source Issues To Publish
 
+This document outlines 20+ contribution opportunities for the Stellar Goal Vault repository.
+
 ## 1. Implement Freighter-signed pledge transactions
+**Difficulty:** Advanced
+**Estimated Effort:** 2 weeks
+**Files to Modify:** `frontend/src/components/PledgeButton.tsx`, `frontend/src/services/stellar.ts`
+**Tags:** enhancement, soroban
 
-Labels:
-- enhancement
-- help wanted
-- soroban
+## 2. Sync campaign activity from Soroban RPC events
+**Difficulty:** Intermediate
+**Estimated Effort:** 1 week
+**Files to Modify:** `backend/src/workers/indexer.ts`, `backend/src/db/schema.sql`
+**Tags:** backend, indexer
 
-Why it matters:
-- this is the biggest missing piece between MVP and real Stellar usage
+## 3. Add filters and sort presets to the dashboard
+**Difficulty:** Beginner
+**Estimated Effort:** 2 days
+**Files to Modify:** `frontend/src/pages/Dashboard.tsx`, `frontend/src/components/FilterBar.tsx`
+**Tags:** frontend, ux, good first issue
 
-Acceptance criteria:
-- contributors sign pledge transactions with Freighter
-- UI shows transaction hash and status
-- timeline displays signed transaction metadata
-- backend can reconcile final pledge state after submission
+## 4. Update README with local setup instructions
+**Difficulty:** Beginner
+**Estimated Effort:** 1 day
+**Files to Modify:** `README.md`
+**Tags:** docs, good first issue
 
-## 2. Sync campaign activity from Soroban RPC events
+## 5. Implement comprehensive unit tests for Campaign creation
+**Difficulty:** Intermediate
+**Estimated Effort:** 3 days
+**Files to Modify:** `backend/tests/unit/campaign.test.ts`
+**Tags:** backend, testing
 
-Labels:
-- backend
-- indexer
-- good first issue
+## 6. Fix mobile layout overflow on Campaign Details page
+**Difficulty:** Beginner
+**Estimated Effort:** 1 day
+**Files to Modify:** `frontend/src/styles/campaignDetails.css`
+**Tags:** frontend, css, good first issue
 
-Acceptance criteria:
-- background worker polls or subscribes to contract events
-- local SQLite state stays aligned with on-chain campaign actions
-- duplicate events are handled safely
+## 7. Refactor Error Handling in API Gateway
+**Difficulty:** Intermediate
+**Estimated Effort:** 1 week
+**Files to Modify:** `backend/src/api/gateway.ts`, `backend/src/utils/errors.ts`
+**Tags:** backend, refactor
 
-## 3. Add filters and sort presets to the dashboard
+## 8. Add GitHub Actions CI for running E2E Playwright tests
+**Difficulty:** Advanced
+**Estimated Effort:** 1.5 weeks
+**Files to Modify:** `.github/workflows/e2e.yml`, `playwright.config.ts`
+**Tags:** ci, testing
+
+## 9. Create a Dark Mode toggle in the Frontend
+**Difficulty:** Intermediate
+**Estimated Effort:** 3 days
+**Files to Modify:** `frontend/src/App.tsx`, `frontend/tailwind.config.js`
+**Tags:** frontend, ux
+
+## 10. Add ESLint and Prettier pre-commit hooks using Husky
+**Difficulty:** Beginner
+**Estimated Effort:** 1 day
+**Files to Modify:** `package.json`, `.husky/pre-commit`
+**Tags:** tooling, good first issue
+
+## 11. Implement Campaign Claim logic for successful campaigns
+**Difficulty:** Advanced
+**Estimated Effort:** 2 weeks
+**Files to Modify:** `contracts/src/campaign.rs`, `contracts/src/lib.rs`
+**Tags:** soroban, rust
+
+## 12. Create API endpoint for fetching campaign analytics
+**Difficulty:** Intermediate
+**Estimated Effort:** 1 week
+**Files to Modify:** `backend/src/controllers/analytics.ts`, `backend/src/routes.ts`
+**Tags:** backend, api
+
+## 13. Localize Frontend strings to Spanish
+**Difficulty:** Beginner
+**Estimated Effort:** 2 days
+**Files to Modify:** `frontend/src/i18n/es.json`
+**Tags:** frontend, i18n, good first issue
+
+## 14. Migrate SQLite to PostgreSQL for production readiness
+**Difficulty:** Advanced
+**Estimated Effort:** 3 weeks
+**Files to Modify:** `backend/src/db/connection.ts`, `docker-compose.yml`
+**Tags:** backend, database
+
+## 15. Standardize button components across the application
+**Difficulty:** Intermediate
+**Estimated Effort:** 3 days
+**Files to Modify:** `frontend/src/components/common/Button.tsx`, `frontend/src/pages/*.tsx`
+**Tags:** frontend, design-system
+
+## 16. Add rate limiting middleware to public API routes
+**Difficulty:** Intermediate
+**Estimated Effort:** 2 days
+**Files to Modify:** `backend/src/middleware/rateLimiter.ts`
+**Tags:** backend, security
+
+## 17. Design and implement a 404 Not Found page
+**Difficulty:** Beginner
+**Estimated Effort:** 1 day
+**Files to Modify:** `frontend/src/pages/NotFound.tsx`, `frontend/src/App.tsx`
+**Tags:** frontend, ux
+
+## 18. Write architecture documentation for Indexer service
+**Difficulty:** Intermediate
+**Estimated Effort:** 1 week
+**Files to Modify:** `docs/INDEXER_ARCHITECTURE.md`
+**Tags:** docs, architecture
+
+## 19. Optimize Docker image sizes by utilizing multi-stage builds
+**Difficulty:** Intermediate
+**Estimated Effort:** 3 days
+**Files to Modify:** `Dockerfile`, `backend/Dockerfile`
+**Tags:** devops, docker
 
-Labels:
-- frontend
-- ux
-- good first issue
+## 20. Implement JWT refresh token rotation
+**Difficulty:** Advanced
+**Estimated Effort:** 2 weeks
+**Files to Modify:** `backend/src/controllers/auth.ts`, `backend/src/middleware/auth.ts`
+**Tags:** backend, security
 
-Acceptance criteria:
-- filter by asset and status
-- sort by deadline, amount raised, and newest
-- query params preserve dashboard state
+## 21. Add user avatar upload feature
+**Difficulty:** Intermediate
+**Estimated Effort:** 1 week
+**Files to Modify:** `frontend/src/components/Profile.tsx`, `backend/src/controllers/user.ts`
+**Tags:** fullstack, feature