feat: add comprehensive E2E test and idempotency for avatar upload

[adnaan]

Summary

This PR improves the avatar upload example to work correctly with the UploadAware interface removal changes and adds comprehensive E2E testing that catches issues missed by browser-based tests.

Changes

Idempotency Fix (main.go)

• Added check to skip processing if temp file already processed
• Prevents errors when upload is processed by both auto-trigger (upload:avatar:complete) and form submit (UpdateProfile)
• Logs clearly indicate when file is skipped

if !fileExists(entry.TempPath) {
    log.Printf("DEBUG: Temp file already processed for entry %s, skipping", entry.ID)
    continue
}

Template Fix (avatar-upload.tmpl)

• Added {{else}} branch to conditional for upload status
• Ensures conditional block always renders content for tree diffing
• Fixes issue where success message wasn't appearing in UI

Comprehensive E2E Test (upload_ws_e2e_test.go) - NEW

• Tests complete WebSocket upload flow: upload_start → upload_chunk → upload_complete
• Validates tree update structure after upload completion
• Verifies success message appears in tree at correct position (position 3)
• Catches issues that chromedp browser-based E2E tests miss
• Direct simulation of browser upload behavior without browser overhead

Dependencies (go.mod/go.sum)

• Updated to use livetemplate with UploadAware removal changes

Test Results

All tests pass including new E2E test that validates:

• ✅ Upload entries are created correctly via WebSocket
• ✅ Tree updates contain full structure for new range items
• ✅ Success message appears at position 3 in the tree
• ✅ Client receives valid tree updates without null/undefined errors

Related

This PR complements #54 which fixes the core library bug that was preventing upload completion messages from appearing.

Test Plan

• New E2E test passes (TestUploadViaWebSocket)
• Idempotency fix prevents double-processing errors
• Template renders success message correctly
• Manual testing confirms upload flow works end-to-end

🤖 Generated with Claude Code

[Copilot]

Pull Request Overview

This PR enhances the avatar upload example with comprehensive E2E testing and idempotency improvements to handle the removal of the UploadAware interface.

Key Changes:

• Adds WebSocket-based E2E test that simulates browser upload behavior without chromedp overhead
• Implements idempotency check to prevent double-processing of uploads when triggered by both auto-completion and form submission
• Fixes template conditional to ensure success messages render correctly in the UI

Reviewed Changes

Copilot reviewed 4 out of 5 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
avatar-upload/upload_ws_e2e_test.go	New comprehensive E2E test using WebSocket protocol to test upload flow and tree updates
avatar-upload/main.go	Refactored upload handling with idempotency checks and auto-trigger support for upload:avatar:complete action
avatar-upload/avatar-upload.tmpl	Added else branch to upload status conditional and upload-status wrapper div for proper rendering
avatar-upload/go.mod	Updated dependencies and Go version (with issues - see comments)
avatar-upload/go.sum	Updated dependency checksums to match go.mod changes

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[Copilot]

The github.com/gorilla/websocket package is used directly in the test file upload_ws_e2e_test.go (line 12) but is listed as an indirect dependency (line 47). It should be moved to the direct dependencies section. See counter/go.mod for the correct pattern where github.com/gorilla/websocket is listed as a direct dependency when used in tests.