Merge branch 'temp-upstream-rebrand' into main

Resolves merge conflicts:
- install.sh, build.sh, .github/workflows/build.yml: Reverted to Dushnilin's versions to avoid installing SourceForge mirrors.
- fe-app-tachyon: Resolved type, formatting and copyOutbound conflicts, keeping both Dushnilin's custom features and ushan0v's frontend performance optimizations.
- backend: Kept Dushnilin's ucode refactorings, Telegram bot integration, and release repository URL (Dushnilin/tachyon) while merging updates.uc cache format v8 & persistent cache format v7.
- tests: Merged tests from both branches, preserving ucode -L wrappers for local test execution.

fe-app-tachyon/package.json

@@ -8,7 +8,7 @@
     "format:js": "prettier --write ../luci-app-tachyon/htdocs/luci-static/resources/view/tachyon",
     "lint": "eslint src --ext .ts,.tsx",
     "lint:fix": "eslint src --ext .ts,.tsx --fix",
-    "build": "tsup src/main.ts",
+    "build": "tsc --noEmit && tsup src/main.ts",
     "dev": "tsup src/main.ts --watch",
     "test": "vitest",
     "ci": "npm run format && npm run lint --max-warnings=0 && npm run test -- --run && npm run build",